1 //===------- SemaTemplateInstantiate.cpp - C++ Template Instantiation ------===/
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //===----------------------------------------------------------------------===/
8 //
9 // This file implements C++ template instantiation.
10 //
11 //===----------------------------------------------------------------------===/
12
13 #include "clang/Sema/SemaInternal.h"
14 #include "TreeTransform.h"
15 #include "clang/AST/ASTConsumer.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/ASTLambda.h"
18 #include "clang/AST/DeclTemplate.h"
19 #include "clang/AST/Expr.h"
20 #include "clang/Basic/LangOptions.h"
21 #include "clang/Sema/DeclSpec.h"
22 #include "clang/Sema/Initialization.h"
23 #include "clang/Sema/Lookup.h"
24 #include "clang/Sema/Template.h"
25 #include "clang/Sema/TemplateDeduction.h"
26
27 using namespace clang;
28 using namespace sema;
29
30 //===----------------------------------------------------------------------===/
31 // Template Instantiation Support
32 //===----------------------------------------------------------------------===/
33
34 /// \brief Retrieve the template argument list(s) that should be used to
35 /// instantiate the definition of the given declaration.
36 ///
37 /// \param D the declaration for which we are computing template instantiation
38 /// arguments.
39 ///
40 /// \param Innermost if non-NULL, the innermost template argument list.
41 ///
42 /// \param RelativeToPrimary true if we should get the template
43 /// arguments relative to the primary template, even when we're
44 /// dealing with a specialization. This is only relevant for function
45 /// template specializations.
46 ///
47 /// \param Pattern If non-NULL, indicates the pattern from which we will be
48 /// instantiating the definition of the given declaration, \p D. This is
49 /// used to determine the proper set of template instantiation arguments for
50 /// friend function template specializations.
51 MultiLevelTemplateArgumentList
getTemplateInstantiationArgs(NamedDecl * D,const TemplateArgumentList * Innermost,bool RelativeToPrimary,const FunctionDecl * Pattern)52 Sema::getTemplateInstantiationArgs(NamedDecl *D,
53 const TemplateArgumentList *Innermost,
54 bool RelativeToPrimary,
55 const FunctionDecl *Pattern) {
56 // Accumulate the set of template argument lists in this structure.
57 MultiLevelTemplateArgumentList Result;
58
59 if (Innermost)
60 Result.addOuterTemplateArguments(Innermost);
61
62 DeclContext *Ctx = dyn_cast<DeclContext>(D);
63 if (!Ctx) {
64 Ctx = D->getDeclContext();
65
66 // Add template arguments from a variable template instantiation.
67 if (VarTemplateSpecializationDecl *Spec =
68 dyn_cast<VarTemplateSpecializationDecl>(D)) {
69 // We're done when we hit an explicit specialization.
70 if (Spec->getSpecializationKind() == TSK_ExplicitSpecialization &&
71 !isa<VarTemplatePartialSpecializationDecl>(Spec))
72 return Result;
73
74 Result.addOuterTemplateArguments(&Spec->getTemplateInstantiationArgs());
75
76 // If this variable template specialization was instantiated from a
77 // specialized member that is a variable template, we're done.
78 assert(Spec->getSpecializedTemplate() && "No variable template?");
79 llvm::PointerUnion<VarTemplateDecl*,
80 VarTemplatePartialSpecializationDecl*> Specialized
81 = Spec->getSpecializedTemplateOrPartial();
82 if (VarTemplatePartialSpecializationDecl *Partial =
83 Specialized.dyn_cast<VarTemplatePartialSpecializationDecl *>()) {
84 if (Partial->isMemberSpecialization())
85 return Result;
86 } else {
87 VarTemplateDecl *Tmpl = Specialized.get<VarTemplateDecl *>();
88 if (Tmpl->isMemberSpecialization())
89 return Result;
90 }
91 }
92
93 // If we have a template template parameter with translation unit context,
94 // then we're performing substitution into a default template argument of
95 // this template template parameter before we've constructed the template
96 // that will own this template template parameter. In this case, we
97 // use empty template parameter lists for all of the outer templates
98 // to avoid performing any substitutions.
99 if (Ctx->isTranslationUnit()) {
100 if (TemplateTemplateParmDecl *TTP
101 = dyn_cast<TemplateTemplateParmDecl>(D)) {
102 for (unsigned I = 0, N = TTP->getDepth() + 1; I != N; ++I)
103 Result.addOuterTemplateArguments(None);
104 return Result;
105 }
106 }
107 }
108
109 while (!Ctx->isFileContext()) {
110 // Add template arguments from a class template instantiation.
111 if (ClassTemplateSpecializationDecl *Spec
112 = dyn_cast<ClassTemplateSpecializationDecl>(Ctx)) {
113 // We're done when we hit an explicit specialization.
114 if (Spec->getSpecializationKind() == TSK_ExplicitSpecialization &&
115 !isa<ClassTemplatePartialSpecializationDecl>(Spec))
116 break;
117
118 Result.addOuterTemplateArguments(&Spec->getTemplateInstantiationArgs());
119
120 // If this class template specialization was instantiated from a
121 // specialized member that is a class template, we're done.
122 assert(Spec->getSpecializedTemplate() && "No class template?");
123 if (Spec->getSpecializedTemplate()->isMemberSpecialization())
124 break;
125 }
126 // Add template arguments from a function template specialization.
127 else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Ctx)) {
128 if (!RelativeToPrimary &&
129 (Function->getTemplateSpecializationKind() ==
130 TSK_ExplicitSpecialization &&
131 !Function->getClassScopeSpecializationPattern()))
132 break;
133
134 if (const TemplateArgumentList *TemplateArgs
135 = Function->getTemplateSpecializationArgs()) {
136 // Add the template arguments for this specialization.
137 Result.addOuterTemplateArguments(TemplateArgs);
138
139 // If this function was instantiated from a specialized member that is
140 // a function template, we're done.
141 assert(Function->getPrimaryTemplate() && "No function template?");
142 if (Function->getPrimaryTemplate()->isMemberSpecialization())
143 break;
144
145 // If this function is a generic lambda specialization, we are done.
146 if (isGenericLambdaCallOperatorSpecialization(Function))
147 break;
148
149 } else if (FunctionTemplateDecl *FunTmpl
150 = Function->getDescribedFunctionTemplate()) {
151 // Add the "injected" template arguments.
152 Result.addOuterTemplateArguments(FunTmpl->getInjectedTemplateArgs());
153 }
154
155 // If this is a friend declaration and it declares an entity at
156 // namespace scope, take arguments from its lexical parent
157 // instead of its semantic parent, unless of course the pattern we're
158 // instantiating actually comes from the file's context!
159 if (Function->getFriendObjectKind() &&
160 Function->getDeclContext()->isFileContext() &&
161 (!Pattern || !Pattern->getLexicalDeclContext()->isFileContext())) {
162 Ctx = Function->getLexicalDeclContext();
163 RelativeToPrimary = false;
164 continue;
165 }
166 } else if (CXXRecordDecl *Rec = dyn_cast<CXXRecordDecl>(Ctx)) {
167 if (ClassTemplateDecl *ClassTemplate = Rec->getDescribedClassTemplate()) {
168 QualType T = ClassTemplate->getInjectedClassNameSpecialization();
169 const TemplateSpecializationType *TST =
170 cast<TemplateSpecializationType>(Context.getCanonicalType(T));
171 Result.addOuterTemplateArguments(
172 llvm::makeArrayRef(TST->getArgs(), TST->getNumArgs()));
173 if (ClassTemplate->isMemberSpecialization())
174 break;
175 }
176 }
177
178 Ctx = Ctx->getParent();
179 RelativeToPrimary = false;
180 }
181
182 return Result;
183 }
184
isInstantiationRecord() const185 bool Sema::ActiveTemplateInstantiation::isInstantiationRecord() const {
186 switch (Kind) {
187 case TemplateInstantiation:
188 case ExceptionSpecInstantiation:
189 case DefaultTemplateArgumentInstantiation:
190 case DefaultFunctionArgumentInstantiation:
191 case ExplicitTemplateArgumentSubstitution:
192 case DeducedTemplateArgumentSubstitution:
193 case PriorTemplateArgumentSubstitution:
194 return true;
195
196 case DefaultTemplateArgumentChecking:
197 return false;
198 }
199
200 llvm_unreachable("Invalid InstantiationKind!");
201 }
202
InstantiatingTemplate(Sema & SemaRef,ActiveTemplateInstantiation::InstantiationKind Kind,SourceLocation PointOfInstantiation,SourceRange InstantiationRange,Decl * Entity,NamedDecl * Template,ArrayRef<TemplateArgument> TemplateArgs,sema::TemplateDeductionInfo * DeductionInfo)203 Sema::InstantiatingTemplate::InstantiatingTemplate(
204 Sema &SemaRef, ActiveTemplateInstantiation::InstantiationKind Kind,
205 SourceLocation PointOfInstantiation, SourceRange InstantiationRange,
206 Decl *Entity, NamedDecl *Template, ArrayRef<TemplateArgument> TemplateArgs,
207 sema::TemplateDeductionInfo *DeductionInfo)
208 : SemaRef(SemaRef), SavedInNonInstantiationSFINAEContext(
209 SemaRef.InNonInstantiationSFINAEContext) {
210 // Don't allow further instantiation if a fatal error has occcured. Any
211 // diagnostics we might have raised will not be visible.
212 if (SemaRef.Diags.hasFatalErrorOccurred()) {
213 Invalid = true;
214 return;
215 }
216 Invalid = CheckInstantiationDepth(PointOfInstantiation, InstantiationRange);
217 if (!Invalid) {
218 ActiveTemplateInstantiation Inst;
219 Inst.Kind = Kind;
220 Inst.PointOfInstantiation = PointOfInstantiation;
221 Inst.Entity = Entity;
222 Inst.Template = Template;
223 Inst.TemplateArgs = TemplateArgs.data();
224 Inst.NumTemplateArgs = TemplateArgs.size();
225 Inst.DeductionInfo = DeductionInfo;
226 Inst.InstantiationRange = InstantiationRange;
227 SemaRef.InNonInstantiationSFINAEContext = false;
228 SemaRef.ActiveTemplateInstantiations.push_back(Inst);
229 if (!Inst.isInstantiationRecord())
230 ++SemaRef.NonInstantiationEntries;
231 }
232 }
233
InstantiatingTemplate(Sema & SemaRef,SourceLocation PointOfInstantiation,Decl * Entity,SourceRange InstantiationRange)234 Sema::InstantiatingTemplate::InstantiatingTemplate(
235 Sema &SemaRef, SourceLocation PointOfInstantiation, Decl *Entity,
236 SourceRange InstantiationRange)
237 : InstantiatingTemplate(SemaRef,
238 ActiveTemplateInstantiation::TemplateInstantiation,
239 PointOfInstantiation, InstantiationRange, Entity) {}
240
InstantiatingTemplate(Sema & SemaRef,SourceLocation PointOfInstantiation,FunctionDecl * Entity,ExceptionSpecification,SourceRange InstantiationRange)241 Sema::InstantiatingTemplate::InstantiatingTemplate(
242 Sema &SemaRef, SourceLocation PointOfInstantiation, FunctionDecl *Entity,
243 ExceptionSpecification, SourceRange InstantiationRange)
244 : InstantiatingTemplate(
245 SemaRef, ActiveTemplateInstantiation::ExceptionSpecInstantiation,
246 PointOfInstantiation, InstantiationRange, Entity) {}
247
InstantiatingTemplate(Sema & SemaRef,SourceLocation PointOfInstantiation,TemplateDecl * Template,ArrayRef<TemplateArgument> TemplateArgs,SourceRange InstantiationRange)248 Sema::InstantiatingTemplate::InstantiatingTemplate(
249 Sema &SemaRef, SourceLocation PointOfInstantiation, TemplateDecl *Template,
250 ArrayRef<TemplateArgument> TemplateArgs, SourceRange InstantiationRange)
251 : InstantiatingTemplate(
252 SemaRef,
253 ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation,
254 PointOfInstantiation, InstantiationRange, Template, nullptr,
255 TemplateArgs) {}
256
InstantiatingTemplate(Sema & SemaRef,SourceLocation PointOfInstantiation,FunctionTemplateDecl * FunctionTemplate,ArrayRef<TemplateArgument> TemplateArgs,ActiveTemplateInstantiation::InstantiationKind Kind,sema::TemplateDeductionInfo & DeductionInfo,SourceRange InstantiationRange)257 Sema::InstantiatingTemplate::InstantiatingTemplate(
258 Sema &SemaRef, SourceLocation PointOfInstantiation,
259 FunctionTemplateDecl *FunctionTemplate,
260 ArrayRef<TemplateArgument> TemplateArgs,
261 ActiveTemplateInstantiation::InstantiationKind Kind,
262 sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
263 : InstantiatingTemplate(SemaRef, Kind, PointOfInstantiation,
264 InstantiationRange, FunctionTemplate, nullptr,
265 TemplateArgs, &DeductionInfo) {}
266
InstantiatingTemplate(Sema & SemaRef,SourceLocation PointOfInstantiation,ClassTemplatePartialSpecializationDecl * PartialSpec,ArrayRef<TemplateArgument> TemplateArgs,sema::TemplateDeductionInfo & DeductionInfo,SourceRange InstantiationRange)267 Sema::InstantiatingTemplate::InstantiatingTemplate(
268 Sema &SemaRef, SourceLocation PointOfInstantiation,
269 ClassTemplatePartialSpecializationDecl *PartialSpec,
270 ArrayRef<TemplateArgument> TemplateArgs,
271 sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
272 : InstantiatingTemplate(
273 SemaRef,
274 ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution,
275 PointOfInstantiation, InstantiationRange, PartialSpec, nullptr,
276 TemplateArgs, &DeductionInfo) {}
277
InstantiatingTemplate(Sema & SemaRef,SourceLocation PointOfInstantiation,VarTemplatePartialSpecializationDecl * PartialSpec,ArrayRef<TemplateArgument> TemplateArgs,sema::TemplateDeductionInfo & DeductionInfo,SourceRange InstantiationRange)278 Sema::InstantiatingTemplate::InstantiatingTemplate(
279 Sema &SemaRef, SourceLocation PointOfInstantiation,
280 VarTemplatePartialSpecializationDecl *PartialSpec,
281 ArrayRef<TemplateArgument> TemplateArgs,
282 sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
283 : InstantiatingTemplate(
284 SemaRef,
285 ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution,
286 PointOfInstantiation, InstantiationRange, PartialSpec, nullptr,
287 TemplateArgs, &DeductionInfo) {}
288
InstantiatingTemplate(Sema & SemaRef,SourceLocation PointOfInstantiation,ParmVarDecl * Param,ArrayRef<TemplateArgument> TemplateArgs,SourceRange InstantiationRange)289 Sema::InstantiatingTemplate::InstantiatingTemplate(
290 Sema &SemaRef, SourceLocation PointOfInstantiation, ParmVarDecl *Param,
291 ArrayRef<TemplateArgument> TemplateArgs, SourceRange InstantiationRange)
292 : InstantiatingTemplate(
293 SemaRef,
294 ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation,
295 PointOfInstantiation, InstantiationRange, Param, nullptr,
296 TemplateArgs) {}
297
InstantiatingTemplate(Sema & SemaRef,SourceLocation PointOfInstantiation,NamedDecl * Template,NonTypeTemplateParmDecl * Param,ArrayRef<TemplateArgument> TemplateArgs,SourceRange InstantiationRange)298 Sema::InstantiatingTemplate::InstantiatingTemplate(
299 Sema &SemaRef, SourceLocation PointOfInstantiation, NamedDecl *Template,
300 NonTypeTemplateParmDecl *Param, ArrayRef<TemplateArgument> TemplateArgs,
301 SourceRange InstantiationRange)
302 : InstantiatingTemplate(
303 SemaRef,
304 ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution,
305 PointOfInstantiation, InstantiationRange, Param, Template,
306 TemplateArgs) {}
307
InstantiatingTemplate(Sema & SemaRef,SourceLocation PointOfInstantiation,NamedDecl * Template,TemplateTemplateParmDecl * Param,ArrayRef<TemplateArgument> TemplateArgs,SourceRange InstantiationRange)308 Sema::InstantiatingTemplate::InstantiatingTemplate(
309 Sema &SemaRef, SourceLocation PointOfInstantiation, NamedDecl *Template,
310 TemplateTemplateParmDecl *Param, ArrayRef<TemplateArgument> TemplateArgs,
311 SourceRange InstantiationRange)
312 : InstantiatingTemplate(
313 SemaRef,
314 ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution,
315 PointOfInstantiation, InstantiationRange, Param, Template,
316 TemplateArgs) {}
317
InstantiatingTemplate(Sema & SemaRef,SourceLocation PointOfInstantiation,TemplateDecl * Template,NamedDecl * Param,ArrayRef<TemplateArgument> TemplateArgs,SourceRange InstantiationRange)318 Sema::InstantiatingTemplate::InstantiatingTemplate(
319 Sema &SemaRef, SourceLocation PointOfInstantiation, TemplateDecl *Template,
320 NamedDecl *Param, ArrayRef<TemplateArgument> TemplateArgs,
321 SourceRange InstantiationRange)
322 : InstantiatingTemplate(
323 SemaRef, ActiveTemplateInstantiation::DefaultTemplateArgumentChecking,
324 PointOfInstantiation, InstantiationRange, Param, Template,
325 TemplateArgs) {}
326
Clear()327 void Sema::InstantiatingTemplate::Clear() {
328 if (!Invalid) {
329 if (!SemaRef.ActiveTemplateInstantiations.back().isInstantiationRecord()) {
330 assert(SemaRef.NonInstantiationEntries > 0);
331 --SemaRef.NonInstantiationEntries;
332 }
333 SemaRef.InNonInstantiationSFINAEContext
334 = SavedInNonInstantiationSFINAEContext;
335
336 // Name lookup no longer looks in this template's defining module.
337 assert(SemaRef.ActiveTemplateInstantiations.size() >=
338 SemaRef.ActiveTemplateInstantiationLookupModules.size() &&
339 "forgot to remove a lookup module for a template instantiation");
340 if (SemaRef.ActiveTemplateInstantiations.size() ==
341 SemaRef.ActiveTemplateInstantiationLookupModules.size()) {
342 if (Module *M = SemaRef.ActiveTemplateInstantiationLookupModules.back())
343 SemaRef.LookupModulesCache.erase(M);
344 SemaRef.ActiveTemplateInstantiationLookupModules.pop_back();
345 }
346
347 SemaRef.ActiveTemplateInstantiations.pop_back();
348 Invalid = true;
349 }
350 }
351
CheckInstantiationDepth(SourceLocation PointOfInstantiation,SourceRange InstantiationRange)352 bool Sema::InstantiatingTemplate::CheckInstantiationDepth(
353 SourceLocation PointOfInstantiation,
354 SourceRange InstantiationRange) {
355 assert(SemaRef.NonInstantiationEntries <=
356 SemaRef.ActiveTemplateInstantiations.size());
357 if ((SemaRef.ActiveTemplateInstantiations.size() -
358 SemaRef.NonInstantiationEntries)
359 <= SemaRef.getLangOpts().InstantiationDepth)
360 return false;
361
362 SemaRef.Diag(PointOfInstantiation,
363 diag::err_template_recursion_depth_exceeded)
364 << SemaRef.getLangOpts().InstantiationDepth
365 << InstantiationRange;
366 SemaRef.Diag(PointOfInstantiation, diag::note_template_recursion_depth)
367 << SemaRef.getLangOpts().InstantiationDepth;
368 return true;
369 }
370
371 /// \brief Prints the current instantiation stack through a series of
372 /// notes.
PrintInstantiationStack()373 void Sema::PrintInstantiationStack() {
374 // Determine which template instantiations to skip, if any.
375 unsigned SkipStart = ActiveTemplateInstantiations.size(), SkipEnd = SkipStart;
376 unsigned Limit = Diags.getTemplateBacktraceLimit();
377 if (Limit && Limit < ActiveTemplateInstantiations.size()) {
378 SkipStart = Limit / 2 + Limit % 2;
379 SkipEnd = ActiveTemplateInstantiations.size() - Limit / 2;
380 }
381
382 // FIXME: In all of these cases, we need to show the template arguments
383 unsigned InstantiationIdx = 0;
384 for (SmallVectorImpl<ActiveTemplateInstantiation>::reverse_iterator
385 Active = ActiveTemplateInstantiations.rbegin(),
386 ActiveEnd = ActiveTemplateInstantiations.rend();
387 Active != ActiveEnd;
388 ++Active, ++InstantiationIdx) {
389 // Skip this instantiation?
390 if (InstantiationIdx >= SkipStart && InstantiationIdx < SkipEnd) {
391 if (InstantiationIdx == SkipStart) {
392 // Note that we're skipping instantiations.
393 Diags.Report(Active->PointOfInstantiation,
394 diag::note_instantiation_contexts_suppressed)
395 << unsigned(ActiveTemplateInstantiations.size() - Limit);
396 }
397 continue;
398 }
399
400 switch (Active->Kind) {
401 case ActiveTemplateInstantiation::TemplateInstantiation: {
402 Decl *D = Active->Entity;
403 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
404 unsigned DiagID = diag::note_template_member_class_here;
405 if (isa<ClassTemplateSpecializationDecl>(Record))
406 DiagID = diag::note_template_class_instantiation_here;
407 Diags.Report(Active->PointOfInstantiation, DiagID)
408 << Context.getTypeDeclType(Record)
409 << Active->InstantiationRange;
410 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) {
411 unsigned DiagID;
412 if (Function->getPrimaryTemplate())
413 DiagID = diag::note_function_template_spec_here;
414 else
415 DiagID = diag::note_template_member_function_here;
416 Diags.Report(Active->PointOfInstantiation, DiagID)
417 << Function
418 << Active->InstantiationRange;
419 } else if (VarDecl *VD = dyn_cast<VarDecl>(D)) {
420 Diags.Report(Active->PointOfInstantiation,
421 VD->isStaticDataMember()?
422 diag::note_template_static_data_member_def_here
423 : diag::note_template_variable_def_here)
424 << VD
425 << Active->InstantiationRange;
426 } else if (EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
427 Diags.Report(Active->PointOfInstantiation,
428 diag::note_template_enum_def_here)
429 << ED
430 << Active->InstantiationRange;
431 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) {
432 Diags.Report(Active->PointOfInstantiation,
433 diag::note_template_nsdmi_here)
434 << FD << Active->InstantiationRange;
435 } else {
436 Diags.Report(Active->PointOfInstantiation,
437 diag::note_template_type_alias_instantiation_here)
438 << cast<TypeAliasTemplateDecl>(D)
439 << Active->InstantiationRange;
440 }
441 break;
442 }
443
444 case ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation: {
445 TemplateDecl *Template = cast<TemplateDecl>(Active->Entity);
446 SmallVector<char, 128> TemplateArgsStr;
447 llvm::raw_svector_ostream OS(TemplateArgsStr);
448 Template->printName(OS);
449 TemplateSpecializationType::PrintTemplateArgumentList(OS,
450 Active->TemplateArgs,
451 Active->NumTemplateArgs,
452 getPrintingPolicy());
453 Diags.Report(Active->PointOfInstantiation,
454 diag::note_default_arg_instantiation_here)
455 << OS.str()
456 << Active->InstantiationRange;
457 break;
458 }
459
460 case ActiveTemplateInstantiation::ExplicitTemplateArgumentSubstitution: {
461 FunctionTemplateDecl *FnTmpl = cast<FunctionTemplateDecl>(Active->Entity);
462 Diags.Report(Active->PointOfInstantiation,
463 diag::note_explicit_template_arg_substitution_here)
464 << FnTmpl
465 << getTemplateArgumentBindingsText(FnTmpl->getTemplateParameters(),
466 Active->TemplateArgs,
467 Active->NumTemplateArgs)
468 << Active->InstantiationRange;
469 break;
470 }
471
472 case ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution:
473 if (ClassTemplatePartialSpecializationDecl *PartialSpec =
474 dyn_cast<ClassTemplatePartialSpecializationDecl>(Active->Entity)) {
475 Diags.Report(Active->PointOfInstantiation,
476 diag::note_partial_spec_deduct_instantiation_here)
477 << Context.getTypeDeclType(PartialSpec)
478 << getTemplateArgumentBindingsText(
479 PartialSpec->getTemplateParameters(),
480 Active->TemplateArgs,
481 Active->NumTemplateArgs)
482 << Active->InstantiationRange;
483 } else {
484 FunctionTemplateDecl *FnTmpl
485 = cast<FunctionTemplateDecl>(Active->Entity);
486 Diags.Report(Active->PointOfInstantiation,
487 diag::note_function_template_deduction_instantiation_here)
488 << FnTmpl
489 << getTemplateArgumentBindingsText(FnTmpl->getTemplateParameters(),
490 Active->TemplateArgs,
491 Active->NumTemplateArgs)
492 << Active->InstantiationRange;
493 }
494 break;
495
496 case ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation: {
497 ParmVarDecl *Param = cast<ParmVarDecl>(Active->Entity);
498 FunctionDecl *FD = cast<FunctionDecl>(Param->getDeclContext());
499
500 SmallVector<char, 128> TemplateArgsStr;
501 llvm::raw_svector_ostream OS(TemplateArgsStr);
502 FD->printName(OS);
503 TemplateSpecializationType::PrintTemplateArgumentList(OS,
504 Active->TemplateArgs,
505 Active->NumTemplateArgs,
506 getPrintingPolicy());
507 Diags.Report(Active->PointOfInstantiation,
508 diag::note_default_function_arg_instantiation_here)
509 << OS.str()
510 << Active->InstantiationRange;
511 break;
512 }
513
514 case ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution: {
515 NamedDecl *Parm = cast<NamedDecl>(Active->Entity);
516 std::string Name;
517 if (!Parm->getName().empty())
518 Name = std::string(" '") + Parm->getName().str() + "'";
519
520 TemplateParameterList *TemplateParams = nullptr;
521 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(Active->Template))
522 TemplateParams = Template->getTemplateParameters();
523 else
524 TemplateParams =
525 cast<ClassTemplatePartialSpecializationDecl>(Active->Template)
526 ->getTemplateParameters();
527 Diags.Report(Active->PointOfInstantiation,
528 diag::note_prior_template_arg_substitution)
529 << isa<TemplateTemplateParmDecl>(Parm)
530 << Name
531 << getTemplateArgumentBindingsText(TemplateParams,
532 Active->TemplateArgs,
533 Active->NumTemplateArgs)
534 << Active->InstantiationRange;
535 break;
536 }
537
538 case ActiveTemplateInstantiation::DefaultTemplateArgumentChecking: {
539 TemplateParameterList *TemplateParams = nullptr;
540 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(Active->Template))
541 TemplateParams = Template->getTemplateParameters();
542 else
543 TemplateParams =
544 cast<ClassTemplatePartialSpecializationDecl>(Active->Template)
545 ->getTemplateParameters();
546
547 Diags.Report(Active->PointOfInstantiation,
548 diag::note_template_default_arg_checking)
549 << getTemplateArgumentBindingsText(TemplateParams,
550 Active->TemplateArgs,
551 Active->NumTemplateArgs)
552 << Active->InstantiationRange;
553 break;
554 }
555
556 case ActiveTemplateInstantiation::ExceptionSpecInstantiation:
557 Diags.Report(Active->PointOfInstantiation,
558 diag::note_template_exception_spec_instantiation_here)
559 << cast<FunctionDecl>(Active->Entity)
560 << Active->InstantiationRange;
561 break;
562 }
563 }
564 }
565
isSFINAEContext() const566 Optional<TemplateDeductionInfo *> Sema::isSFINAEContext() const {
567 if (InNonInstantiationSFINAEContext)
568 return Optional<TemplateDeductionInfo *>(nullptr);
569
570 for (SmallVectorImpl<ActiveTemplateInstantiation>::const_reverse_iterator
571 Active = ActiveTemplateInstantiations.rbegin(),
572 ActiveEnd = ActiveTemplateInstantiations.rend();
573 Active != ActiveEnd;
574 ++Active)
575 {
576 switch(Active->Kind) {
577 case ActiveTemplateInstantiation::TemplateInstantiation:
578 // An instantiation of an alias template may or may not be a SFINAE
579 // context, depending on what else is on the stack.
580 if (isa<TypeAliasTemplateDecl>(Active->Entity))
581 break;
582 // Fall through.
583 case ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation:
584 case ActiveTemplateInstantiation::ExceptionSpecInstantiation:
585 // This is a template instantiation, so there is no SFINAE.
586 return None;
587
588 case ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation:
589 case ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution:
590 case ActiveTemplateInstantiation::DefaultTemplateArgumentChecking:
591 // A default template argument instantiation and substitution into
592 // template parameters with arguments for prior parameters may or may
593 // not be a SFINAE context; look further up the stack.
594 break;
595
596 case ActiveTemplateInstantiation::ExplicitTemplateArgumentSubstitution:
597 case ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution:
598 // We're either substitution explicitly-specified template arguments
599 // or deduced template arguments, so SFINAE applies.
600 assert(Active->DeductionInfo && "Missing deduction info pointer");
601 return Active->DeductionInfo;
602 }
603 }
604
605 return None;
606 }
607
608 /// \brief Retrieve the depth and index of a parameter pack.
609 static std::pair<unsigned, unsigned>
getDepthAndIndex(NamedDecl * ND)610 getDepthAndIndex(NamedDecl *ND) {
611 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(ND))
612 return std::make_pair(TTP->getDepth(), TTP->getIndex());
613
614 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(ND))
615 return std::make_pair(NTTP->getDepth(), NTTP->getIndex());
616
617 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(ND);
618 return std::make_pair(TTP->getDepth(), TTP->getIndex());
619 }
620
621 //===----------------------------------------------------------------------===/
622 // Template Instantiation for Types
623 //===----------------------------------------------------------------------===/
624 namespace {
625 class TemplateInstantiator : public TreeTransform<TemplateInstantiator> {
626 const MultiLevelTemplateArgumentList &TemplateArgs;
627 SourceLocation Loc;
628 DeclarationName Entity;
629
630 public:
631 typedef TreeTransform<TemplateInstantiator> inherited;
632
TemplateInstantiator(Sema & SemaRef,const MultiLevelTemplateArgumentList & TemplateArgs,SourceLocation Loc,DeclarationName Entity)633 TemplateInstantiator(Sema &SemaRef,
634 const MultiLevelTemplateArgumentList &TemplateArgs,
635 SourceLocation Loc,
636 DeclarationName Entity)
637 : inherited(SemaRef), TemplateArgs(TemplateArgs), Loc(Loc),
638 Entity(Entity) { }
639
640 /// \brief Determine whether the given type \p T has already been
641 /// transformed.
642 ///
643 /// For the purposes of template instantiation, a type has already been
644 /// transformed if it is NULL or if it is not dependent.
645 bool AlreadyTransformed(QualType T);
646
647 /// \brief Returns the location of the entity being instantiated, if known.
getBaseLocation()648 SourceLocation getBaseLocation() { return Loc; }
649
650 /// \brief Returns the name of the entity being instantiated, if any.
getBaseEntity()651 DeclarationName getBaseEntity() { return Entity; }
652
653 /// \brief Sets the "base" location and entity when that
654 /// information is known based on another transformation.
setBase(SourceLocation Loc,DeclarationName Entity)655 void setBase(SourceLocation Loc, DeclarationName Entity) {
656 this->Loc = Loc;
657 this->Entity = Entity;
658 }
659
TryExpandParameterPacks(SourceLocation EllipsisLoc,SourceRange PatternRange,ArrayRef<UnexpandedParameterPack> Unexpanded,bool & ShouldExpand,bool & RetainExpansion,Optional<unsigned> & NumExpansions)660 bool TryExpandParameterPacks(SourceLocation EllipsisLoc,
661 SourceRange PatternRange,
662 ArrayRef<UnexpandedParameterPack> Unexpanded,
663 bool &ShouldExpand, bool &RetainExpansion,
664 Optional<unsigned> &NumExpansions) {
665 return getSema().CheckParameterPacksForExpansion(EllipsisLoc,
666 PatternRange, Unexpanded,
667 TemplateArgs,
668 ShouldExpand,
669 RetainExpansion,
670 NumExpansions);
671 }
672
ExpandingFunctionParameterPack(ParmVarDecl * Pack)673 void ExpandingFunctionParameterPack(ParmVarDecl *Pack) {
674 SemaRef.CurrentInstantiationScope->MakeInstantiatedLocalArgPack(Pack);
675 }
676
ForgetPartiallySubstitutedPack()677 TemplateArgument ForgetPartiallySubstitutedPack() {
678 TemplateArgument Result;
679 if (NamedDecl *PartialPack
680 = SemaRef.CurrentInstantiationScope->getPartiallySubstitutedPack()){
681 MultiLevelTemplateArgumentList &TemplateArgs
682 = const_cast<MultiLevelTemplateArgumentList &>(this->TemplateArgs);
683 unsigned Depth, Index;
684 std::tie(Depth, Index) = getDepthAndIndex(PartialPack);
685 if (TemplateArgs.hasTemplateArgument(Depth, Index)) {
686 Result = TemplateArgs(Depth, Index);
687 TemplateArgs.setArgument(Depth, Index, TemplateArgument());
688 }
689 }
690
691 return Result;
692 }
693
RememberPartiallySubstitutedPack(TemplateArgument Arg)694 void RememberPartiallySubstitutedPack(TemplateArgument Arg) {
695 if (Arg.isNull())
696 return;
697
698 if (NamedDecl *PartialPack
699 = SemaRef.CurrentInstantiationScope->getPartiallySubstitutedPack()){
700 MultiLevelTemplateArgumentList &TemplateArgs
701 = const_cast<MultiLevelTemplateArgumentList &>(this->TemplateArgs);
702 unsigned Depth, Index;
703 std::tie(Depth, Index) = getDepthAndIndex(PartialPack);
704 TemplateArgs.setArgument(Depth, Index, Arg);
705 }
706 }
707
708 /// \brief Transform the given declaration by instantiating a reference to
709 /// this declaration.
710 Decl *TransformDecl(SourceLocation Loc, Decl *D);
711
transformAttrs(Decl * Old,Decl * New)712 void transformAttrs(Decl *Old, Decl *New) {
713 SemaRef.InstantiateAttrs(TemplateArgs, Old, New);
714 }
715
transformedLocalDecl(Decl * Old,Decl * New)716 void transformedLocalDecl(Decl *Old, Decl *New) {
717 // If we've instantiated the call operator of a lambda or the call
718 // operator template of a generic lambda, update the "instantiation of"
719 // information.
720 auto *NewMD = dyn_cast<CXXMethodDecl>(New);
721 if (NewMD && isLambdaCallOperator(NewMD)) {
722 auto *OldMD = dyn_cast<CXXMethodDecl>(Old);
723 if (auto *NewTD = NewMD->getDescribedFunctionTemplate())
724 NewTD->setInstantiatedFromMemberTemplate(
725 OldMD->getDescribedFunctionTemplate());
726 else
727 NewMD->setInstantiationOfMemberFunction(OldMD,
728 TSK_ImplicitInstantiation);
729 }
730
731 SemaRef.CurrentInstantiationScope->InstantiatedLocal(Old, New);
732 }
733
734 /// \brief Transform the definition of the given declaration by
735 /// instantiating it.
736 Decl *TransformDefinition(SourceLocation Loc, Decl *D);
737
738 /// \brief Transform the first qualifier within a scope by instantiating the
739 /// declaration.
740 NamedDecl *TransformFirstQualifierInScope(NamedDecl *D, SourceLocation Loc);
741
742 /// \brief Rebuild the exception declaration and register the declaration
743 /// as an instantiated local.
744 VarDecl *RebuildExceptionDecl(VarDecl *ExceptionDecl,
745 TypeSourceInfo *Declarator,
746 SourceLocation StartLoc,
747 SourceLocation NameLoc,
748 IdentifierInfo *Name);
749
750 /// \brief Rebuild the Objective-C exception declaration and register the
751 /// declaration as an instantiated local.
752 VarDecl *RebuildObjCExceptionDecl(VarDecl *ExceptionDecl,
753 TypeSourceInfo *TSInfo, QualType T);
754
755 /// \brief Check for tag mismatches when instantiating an
756 /// elaborated type.
757 QualType RebuildElaboratedType(SourceLocation KeywordLoc,
758 ElaboratedTypeKeyword Keyword,
759 NestedNameSpecifierLoc QualifierLoc,
760 QualType T);
761
762 TemplateName
763 TransformTemplateName(CXXScopeSpec &SS, TemplateName Name,
764 SourceLocation NameLoc,
765 QualType ObjectType = QualType(),
766 NamedDecl *FirstQualifierInScope = nullptr);
767
768 const LoopHintAttr *TransformLoopHintAttr(const LoopHintAttr *LH);
769
770 ExprResult TransformPredefinedExpr(PredefinedExpr *E);
771 ExprResult TransformDeclRefExpr(DeclRefExpr *E);
772 ExprResult TransformCXXDefaultArgExpr(CXXDefaultArgExpr *E);
773
774 ExprResult TransformTemplateParmRefExpr(DeclRefExpr *E,
775 NonTypeTemplateParmDecl *D);
776 ExprResult TransformSubstNonTypeTemplateParmPackExpr(
777 SubstNonTypeTemplateParmPackExpr *E);
778
779 /// \brief Rebuild a DeclRefExpr for a ParmVarDecl reference.
780 ExprResult RebuildParmVarDeclRefExpr(ParmVarDecl *PD, SourceLocation Loc);
781
782 /// \brief Transform a reference to a function parameter pack.
783 ExprResult TransformFunctionParmPackRefExpr(DeclRefExpr *E,
784 ParmVarDecl *PD);
785
786 /// \brief Transform a FunctionParmPackExpr which was built when we couldn't
787 /// expand a function parameter pack reference which refers to an expanded
788 /// pack.
789 ExprResult TransformFunctionParmPackExpr(FunctionParmPackExpr *E);
790
TransformFunctionProtoType(TypeLocBuilder & TLB,FunctionProtoTypeLoc TL)791 QualType TransformFunctionProtoType(TypeLocBuilder &TLB,
792 FunctionProtoTypeLoc TL) {
793 // Call the base version; it will forward to our overridden version below.
794 return inherited::TransformFunctionProtoType(TLB, TL);
795 }
796
797 template<typename Fn>
798 QualType TransformFunctionProtoType(TypeLocBuilder &TLB,
799 FunctionProtoTypeLoc TL,
800 CXXRecordDecl *ThisContext,
801 unsigned ThisTypeQuals,
802 Fn TransformExceptionSpec);
803
804 ParmVarDecl *TransformFunctionTypeParam(ParmVarDecl *OldParm,
805 int indexAdjustment,
806 Optional<unsigned> NumExpansions,
807 bool ExpectParameterPack);
808
809 /// \brief Transforms a template type parameter type by performing
810 /// substitution of the corresponding template type argument.
811 QualType TransformTemplateTypeParmType(TypeLocBuilder &TLB,
812 TemplateTypeParmTypeLoc TL);
813
814 /// \brief Transforms an already-substituted template type parameter pack
815 /// into either itself (if we aren't substituting into its pack expansion)
816 /// or the appropriate substituted argument.
817 QualType TransformSubstTemplateTypeParmPackType(TypeLocBuilder &TLB,
818 SubstTemplateTypeParmPackTypeLoc TL);
819
TransformLambdaExpr(LambdaExpr * E)820 ExprResult TransformLambdaExpr(LambdaExpr *E) {
821 LocalInstantiationScope Scope(SemaRef, /*CombineWithOuterScope=*/true);
822 return TreeTransform<TemplateInstantiator>::TransformLambdaExpr(E);
823 }
824
TransformTemplateParameterList(TemplateParameterList * OrigTPL)825 TemplateParameterList *TransformTemplateParameterList(
826 TemplateParameterList *OrigTPL) {
827 if (!OrigTPL || !OrigTPL->size()) return OrigTPL;
828
829 DeclContext *Owner = OrigTPL->getParam(0)->getDeclContext();
830 TemplateDeclInstantiator DeclInstantiator(getSema(),
831 /* DeclContext *Owner */ Owner, TemplateArgs);
832 return DeclInstantiator.SubstTemplateParams(OrigTPL);
833 }
834 private:
835 ExprResult transformNonTypeTemplateParmRef(NonTypeTemplateParmDecl *parm,
836 SourceLocation loc,
837 TemplateArgument arg);
838 };
839 }
840
AlreadyTransformed(QualType T)841 bool TemplateInstantiator::AlreadyTransformed(QualType T) {
842 if (T.isNull())
843 return true;
844
845 if (T->isInstantiationDependentType() || T->isVariablyModifiedType())
846 return false;
847
848 getSema().MarkDeclarationsReferencedInType(Loc, T);
849 return true;
850 }
851
852 static TemplateArgument
getPackSubstitutedTemplateArgument(Sema & S,TemplateArgument Arg)853 getPackSubstitutedTemplateArgument(Sema &S, TemplateArgument Arg) {
854 assert(S.ArgumentPackSubstitutionIndex >= 0);
855 assert(S.ArgumentPackSubstitutionIndex < (int)Arg.pack_size());
856 Arg = Arg.pack_begin()[S.ArgumentPackSubstitutionIndex];
857 if (Arg.isPackExpansion())
858 Arg = Arg.getPackExpansionPattern();
859 return Arg;
860 }
861
TransformDecl(SourceLocation Loc,Decl * D)862 Decl *TemplateInstantiator::TransformDecl(SourceLocation Loc, Decl *D) {
863 if (!D)
864 return nullptr;
865
866 if (TemplateTemplateParmDecl *TTP = dyn_cast<TemplateTemplateParmDecl>(D)) {
867 if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
868 // If the corresponding template argument is NULL or non-existent, it's
869 // because we are performing instantiation from explicitly-specified
870 // template arguments in a function template, but there were some
871 // arguments left unspecified.
872 if (!TemplateArgs.hasTemplateArgument(TTP->getDepth(),
873 TTP->getPosition()))
874 return D;
875
876 TemplateArgument Arg = TemplateArgs(TTP->getDepth(), TTP->getPosition());
877
878 if (TTP->isParameterPack()) {
879 assert(Arg.getKind() == TemplateArgument::Pack &&
880 "Missing argument pack");
881 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
882 }
883
884 TemplateName Template = Arg.getAsTemplate();
885 assert(!Template.isNull() && Template.getAsTemplateDecl() &&
886 "Wrong kind of template template argument");
887 return Template.getAsTemplateDecl();
888 }
889
890 // Fall through to find the instantiated declaration for this template
891 // template parameter.
892 }
893
894 return SemaRef.FindInstantiatedDecl(Loc, cast<NamedDecl>(D), TemplateArgs);
895 }
896
TransformDefinition(SourceLocation Loc,Decl * D)897 Decl *TemplateInstantiator::TransformDefinition(SourceLocation Loc, Decl *D) {
898 Decl *Inst = getSema().SubstDecl(D, getSema().CurContext, TemplateArgs);
899 if (!Inst)
900 return nullptr;
901
902 getSema().CurrentInstantiationScope->InstantiatedLocal(D, Inst);
903 return Inst;
904 }
905
906 NamedDecl *
TransformFirstQualifierInScope(NamedDecl * D,SourceLocation Loc)907 TemplateInstantiator::TransformFirstQualifierInScope(NamedDecl *D,
908 SourceLocation Loc) {
909 // If the first part of the nested-name-specifier was a template type
910 // parameter, instantiate that type parameter down to a tag type.
911 if (TemplateTypeParmDecl *TTPD = dyn_cast_or_null<TemplateTypeParmDecl>(D)) {
912 const TemplateTypeParmType *TTP
913 = cast<TemplateTypeParmType>(getSema().Context.getTypeDeclType(TTPD));
914
915 if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
916 // FIXME: This needs testing w/ member access expressions.
917 TemplateArgument Arg = TemplateArgs(TTP->getDepth(), TTP->getIndex());
918
919 if (TTP->isParameterPack()) {
920 assert(Arg.getKind() == TemplateArgument::Pack &&
921 "Missing argument pack");
922
923 if (getSema().ArgumentPackSubstitutionIndex == -1)
924 return nullptr;
925
926 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
927 }
928
929 QualType T = Arg.getAsType();
930 if (T.isNull())
931 return cast_or_null<NamedDecl>(TransformDecl(Loc, D));
932
933 if (const TagType *Tag = T->getAs<TagType>())
934 return Tag->getDecl();
935
936 // The resulting type is not a tag; complain.
937 getSema().Diag(Loc, diag::err_nested_name_spec_non_tag) << T;
938 return nullptr;
939 }
940 }
941
942 return cast_or_null<NamedDecl>(TransformDecl(Loc, D));
943 }
944
945 VarDecl *
RebuildExceptionDecl(VarDecl * ExceptionDecl,TypeSourceInfo * Declarator,SourceLocation StartLoc,SourceLocation NameLoc,IdentifierInfo * Name)946 TemplateInstantiator::RebuildExceptionDecl(VarDecl *ExceptionDecl,
947 TypeSourceInfo *Declarator,
948 SourceLocation StartLoc,
949 SourceLocation NameLoc,
950 IdentifierInfo *Name) {
951 VarDecl *Var = inherited::RebuildExceptionDecl(ExceptionDecl, Declarator,
952 StartLoc, NameLoc, Name);
953 if (Var)
954 getSema().CurrentInstantiationScope->InstantiatedLocal(ExceptionDecl, Var);
955 return Var;
956 }
957
RebuildObjCExceptionDecl(VarDecl * ExceptionDecl,TypeSourceInfo * TSInfo,QualType T)958 VarDecl *TemplateInstantiator::RebuildObjCExceptionDecl(VarDecl *ExceptionDecl,
959 TypeSourceInfo *TSInfo,
960 QualType T) {
961 VarDecl *Var = inherited::RebuildObjCExceptionDecl(ExceptionDecl, TSInfo, T);
962 if (Var)
963 getSema().CurrentInstantiationScope->InstantiatedLocal(ExceptionDecl, Var);
964 return Var;
965 }
966
967 QualType
RebuildElaboratedType(SourceLocation KeywordLoc,ElaboratedTypeKeyword Keyword,NestedNameSpecifierLoc QualifierLoc,QualType T)968 TemplateInstantiator::RebuildElaboratedType(SourceLocation KeywordLoc,
969 ElaboratedTypeKeyword Keyword,
970 NestedNameSpecifierLoc QualifierLoc,
971 QualType T) {
972 if (const TagType *TT = T->getAs<TagType>()) {
973 TagDecl* TD = TT->getDecl();
974
975 SourceLocation TagLocation = KeywordLoc;
976
977 IdentifierInfo *Id = TD->getIdentifier();
978
979 // TODO: should we even warn on struct/class mismatches for this? Seems
980 // like it's likely to produce a lot of spurious errors.
981 if (Id && Keyword != ETK_None && Keyword != ETK_Typename) {
982 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForKeyword(Keyword);
983 if (!SemaRef.isAcceptableTagRedeclaration(TD, Kind, /*isDefinition*/false,
984 TagLocation, Id)) {
985 SemaRef.Diag(TagLocation, diag::err_use_with_wrong_tag)
986 << Id
987 << FixItHint::CreateReplacement(SourceRange(TagLocation),
988 TD->getKindName());
989 SemaRef.Diag(TD->getLocation(), diag::note_previous_use);
990 }
991 }
992 }
993
994 return TreeTransform<TemplateInstantiator>::RebuildElaboratedType(KeywordLoc,
995 Keyword,
996 QualifierLoc,
997 T);
998 }
999
TransformTemplateName(CXXScopeSpec & SS,TemplateName Name,SourceLocation NameLoc,QualType ObjectType,NamedDecl * FirstQualifierInScope)1000 TemplateName TemplateInstantiator::TransformTemplateName(CXXScopeSpec &SS,
1001 TemplateName Name,
1002 SourceLocation NameLoc,
1003 QualType ObjectType,
1004 NamedDecl *FirstQualifierInScope) {
1005 if (TemplateTemplateParmDecl *TTP
1006 = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())) {
1007 if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
1008 // If the corresponding template argument is NULL or non-existent, it's
1009 // because we are performing instantiation from explicitly-specified
1010 // template arguments in a function template, but there were some
1011 // arguments left unspecified.
1012 if (!TemplateArgs.hasTemplateArgument(TTP->getDepth(),
1013 TTP->getPosition()))
1014 return Name;
1015
1016 TemplateArgument Arg = TemplateArgs(TTP->getDepth(), TTP->getPosition());
1017
1018 if (TTP->isParameterPack()) {
1019 assert(Arg.getKind() == TemplateArgument::Pack &&
1020 "Missing argument pack");
1021
1022 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1023 // We have the template argument pack to substitute, but we're not
1024 // actually expanding the enclosing pack expansion yet. So, just
1025 // keep the entire argument pack.
1026 return getSema().Context.getSubstTemplateTemplateParmPack(TTP, Arg);
1027 }
1028
1029 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1030 }
1031
1032 TemplateName Template = Arg.getAsTemplate();
1033 assert(!Template.isNull() && "Null template template argument");
1034
1035 // We don't ever want to substitute for a qualified template name, since
1036 // the qualifier is handled separately. So, look through the qualified
1037 // template name to its underlying declaration.
1038 if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
1039 Template = TemplateName(QTN->getTemplateDecl());
1040
1041 Template = getSema().Context.getSubstTemplateTemplateParm(TTP, Template);
1042 return Template;
1043 }
1044 }
1045
1046 if (SubstTemplateTemplateParmPackStorage *SubstPack
1047 = Name.getAsSubstTemplateTemplateParmPack()) {
1048 if (getSema().ArgumentPackSubstitutionIndex == -1)
1049 return Name;
1050
1051 TemplateArgument Arg = SubstPack->getArgumentPack();
1052 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1053 return Arg.getAsTemplate();
1054 }
1055
1056 return inherited::TransformTemplateName(SS, Name, NameLoc, ObjectType,
1057 FirstQualifierInScope);
1058 }
1059
1060 ExprResult
TransformPredefinedExpr(PredefinedExpr * E)1061 TemplateInstantiator::TransformPredefinedExpr(PredefinedExpr *E) {
1062 if (!E->isTypeDependent())
1063 return E;
1064
1065 return getSema().BuildPredefinedExpr(E->getLocation(), E->getIdentType());
1066 }
1067
1068 ExprResult
TransformTemplateParmRefExpr(DeclRefExpr * E,NonTypeTemplateParmDecl * NTTP)1069 TemplateInstantiator::TransformTemplateParmRefExpr(DeclRefExpr *E,
1070 NonTypeTemplateParmDecl *NTTP) {
1071 // If the corresponding template argument is NULL or non-existent, it's
1072 // because we are performing instantiation from explicitly-specified
1073 // template arguments in a function template, but there were some
1074 // arguments left unspecified.
1075 if (!TemplateArgs.hasTemplateArgument(NTTP->getDepth(),
1076 NTTP->getPosition()))
1077 return E;
1078
1079 TemplateArgument Arg = TemplateArgs(NTTP->getDepth(), NTTP->getPosition());
1080 if (NTTP->isParameterPack()) {
1081 assert(Arg.getKind() == TemplateArgument::Pack &&
1082 "Missing argument pack");
1083
1084 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1085 // We have an argument pack, but we can't select a particular argument
1086 // out of it yet. Therefore, we'll build an expression to hold on to that
1087 // argument pack.
1088 QualType TargetType = SemaRef.SubstType(NTTP->getType(), TemplateArgs,
1089 E->getLocation(),
1090 NTTP->getDeclName());
1091 if (TargetType.isNull())
1092 return ExprError();
1093
1094 return new (SemaRef.Context) SubstNonTypeTemplateParmPackExpr(TargetType,
1095 NTTP,
1096 E->getLocation(),
1097 Arg);
1098 }
1099
1100 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1101 }
1102
1103 return transformNonTypeTemplateParmRef(NTTP, E->getLocation(), Arg);
1104 }
1105
1106 const LoopHintAttr *
TransformLoopHintAttr(const LoopHintAttr * LH)1107 TemplateInstantiator::TransformLoopHintAttr(const LoopHintAttr *LH) {
1108 Expr *TransformedExpr = getDerived().TransformExpr(LH->getValue()).get();
1109
1110 if (TransformedExpr == LH->getValue())
1111 return LH;
1112
1113 // Generate error if there is a problem with the value.
1114 if (getSema().CheckLoopHintExpr(TransformedExpr, LH->getLocation()))
1115 return LH;
1116
1117 // Create new LoopHintValueAttr with integral expression in place of the
1118 // non-type template parameter.
1119 return LoopHintAttr::CreateImplicit(
1120 getSema().Context, LH->getSemanticSpelling(), LH->getOption(),
1121 LH->getState(), TransformedExpr, LH->getRange());
1122 }
1123
transformNonTypeTemplateParmRef(NonTypeTemplateParmDecl * parm,SourceLocation loc,TemplateArgument arg)1124 ExprResult TemplateInstantiator::transformNonTypeTemplateParmRef(
1125 NonTypeTemplateParmDecl *parm,
1126 SourceLocation loc,
1127 TemplateArgument arg) {
1128 ExprResult result;
1129 QualType type;
1130
1131 // The template argument itself might be an expression, in which
1132 // case we just return that expression.
1133 if (arg.getKind() == TemplateArgument::Expression) {
1134 Expr *argExpr = arg.getAsExpr();
1135 result = argExpr;
1136 type = argExpr->getType();
1137
1138 } else if (arg.getKind() == TemplateArgument::Declaration ||
1139 arg.getKind() == TemplateArgument::NullPtr) {
1140 ValueDecl *VD;
1141 if (arg.getKind() == TemplateArgument::Declaration) {
1142 VD = cast<ValueDecl>(arg.getAsDecl());
1143
1144 // Find the instantiation of the template argument. This is
1145 // required for nested templates.
1146 VD = cast_or_null<ValueDecl>(
1147 getSema().FindInstantiatedDecl(loc, VD, TemplateArgs));
1148 if (!VD)
1149 return ExprError();
1150 } else {
1151 // Propagate NULL template argument.
1152 VD = nullptr;
1153 }
1154
1155 // Derive the type we want the substituted decl to have. This had
1156 // better be non-dependent, or these checks will have serious problems.
1157 if (parm->isExpandedParameterPack()) {
1158 type = parm->getExpansionType(SemaRef.ArgumentPackSubstitutionIndex);
1159 } else if (parm->isParameterPack() &&
1160 isa<PackExpansionType>(parm->getType())) {
1161 type = SemaRef.SubstType(
1162 cast<PackExpansionType>(parm->getType())->getPattern(),
1163 TemplateArgs, loc, parm->getDeclName());
1164 } else {
1165 type = SemaRef.SubstType(parm->getType(), TemplateArgs,
1166 loc, parm->getDeclName());
1167 }
1168 assert(!type.isNull() && "type substitution failed for param type");
1169 assert(!type->isDependentType() && "param type still dependent");
1170 result = SemaRef.BuildExpressionFromDeclTemplateArgument(arg, type, loc);
1171
1172 if (!result.isInvalid()) type = result.get()->getType();
1173 } else {
1174 result = SemaRef.BuildExpressionFromIntegralTemplateArgument(arg, loc);
1175
1176 // Note that this type can be different from the type of 'result',
1177 // e.g. if it's an enum type.
1178 type = arg.getIntegralType();
1179 }
1180 if (result.isInvalid()) return ExprError();
1181
1182 Expr *resultExpr = result.get();
1183 return new (SemaRef.Context) SubstNonTypeTemplateParmExpr(
1184 type, resultExpr->getValueKind(), loc, parm, resultExpr);
1185 }
1186
1187 ExprResult
TransformSubstNonTypeTemplateParmPackExpr(SubstNonTypeTemplateParmPackExpr * E)1188 TemplateInstantiator::TransformSubstNonTypeTemplateParmPackExpr(
1189 SubstNonTypeTemplateParmPackExpr *E) {
1190 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1191 // We aren't expanding the parameter pack, so just return ourselves.
1192 return E;
1193 }
1194
1195 TemplateArgument Arg = E->getArgumentPack();
1196 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1197 return transformNonTypeTemplateParmRef(E->getParameterPack(),
1198 E->getParameterPackLocation(),
1199 Arg);
1200 }
1201
1202 ExprResult
RebuildParmVarDeclRefExpr(ParmVarDecl * PD,SourceLocation Loc)1203 TemplateInstantiator::RebuildParmVarDeclRefExpr(ParmVarDecl *PD,
1204 SourceLocation Loc) {
1205 DeclarationNameInfo NameInfo(PD->getDeclName(), Loc);
1206 return getSema().BuildDeclarationNameExpr(CXXScopeSpec(), NameInfo, PD);
1207 }
1208
1209 ExprResult
TransformFunctionParmPackExpr(FunctionParmPackExpr * E)1210 TemplateInstantiator::TransformFunctionParmPackExpr(FunctionParmPackExpr *E) {
1211 if (getSema().ArgumentPackSubstitutionIndex != -1) {
1212 // We can expand this parameter pack now.
1213 ParmVarDecl *D = E->getExpansion(getSema().ArgumentPackSubstitutionIndex);
1214 ValueDecl *VD = cast_or_null<ValueDecl>(TransformDecl(E->getExprLoc(), D));
1215 if (!VD)
1216 return ExprError();
1217 return RebuildParmVarDeclRefExpr(cast<ParmVarDecl>(VD), E->getExprLoc());
1218 }
1219
1220 QualType T = TransformType(E->getType());
1221 if (T.isNull())
1222 return ExprError();
1223
1224 // Transform each of the parameter expansions into the corresponding
1225 // parameters in the instantiation of the function decl.
1226 SmallVector<ParmVarDecl *, 8> Parms;
1227 Parms.reserve(E->getNumExpansions());
1228 for (FunctionParmPackExpr::iterator I = E->begin(), End = E->end();
1229 I != End; ++I) {
1230 ParmVarDecl *D =
1231 cast_or_null<ParmVarDecl>(TransformDecl(E->getExprLoc(), *I));
1232 if (!D)
1233 return ExprError();
1234 Parms.push_back(D);
1235 }
1236
1237 return FunctionParmPackExpr::Create(getSema().Context, T,
1238 E->getParameterPack(),
1239 E->getParameterPackLocation(), Parms);
1240 }
1241
1242 ExprResult
TransformFunctionParmPackRefExpr(DeclRefExpr * E,ParmVarDecl * PD)1243 TemplateInstantiator::TransformFunctionParmPackRefExpr(DeclRefExpr *E,
1244 ParmVarDecl *PD) {
1245 typedef LocalInstantiationScope::DeclArgumentPack DeclArgumentPack;
1246 llvm::PointerUnion<Decl *, DeclArgumentPack *> *Found
1247 = getSema().CurrentInstantiationScope->findInstantiationOf(PD);
1248 assert(Found && "no instantiation for parameter pack");
1249
1250 Decl *TransformedDecl;
1251 if (DeclArgumentPack *Pack = Found->dyn_cast<DeclArgumentPack *>()) {
1252 // If this is a reference to a function parameter pack which we can
1253 // substitute but can't yet expand, build a FunctionParmPackExpr for it.
1254 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1255 QualType T = TransformType(E->getType());
1256 if (T.isNull())
1257 return ExprError();
1258 return FunctionParmPackExpr::Create(getSema().Context, T, PD,
1259 E->getExprLoc(), *Pack);
1260 }
1261
1262 TransformedDecl = (*Pack)[getSema().ArgumentPackSubstitutionIndex];
1263 } else {
1264 TransformedDecl = Found->get<Decl*>();
1265 }
1266
1267 // We have either an unexpanded pack or a specific expansion.
1268 return RebuildParmVarDeclRefExpr(cast<ParmVarDecl>(TransformedDecl),
1269 E->getExprLoc());
1270 }
1271
1272 ExprResult
TransformDeclRefExpr(DeclRefExpr * E)1273 TemplateInstantiator::TransformDeclRefExpr(DeclRefExpr *E) {
1274 NamedDecl *D = E->getDecl();
1275
1276 // Handle references to non-type template parameters and non-type template
1277 // parameter packs.
1278 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(D)) {
1279 if (NTTP->getDepth() < TemplateArgs.getNumLevels())
1280 return TransformTemplateParmRefExpr(E, NTTP);
1281
1282 // We have a non-type template parameter that isn't fully substituted;
1283 // FindInstantiatedDecl will find it in the local instantiation scope.
1284 }
1285
1286 // Handle references to function parameter packs.
1287 if (ParmVarDecl *PD = dyn_cast<ParmVarDecl>(D))
1288 if (PD->isParameterPack())
1289 return TransformFunctionParmPackRefExpr(E, PD);
1290
1291 return TreeTransform<TemplateInstantiator>::TransformDeclRefExpr(E);
1292 }
1293
TransformCXXDefaultArgExpr(CXXDefaultArgExpr * E)1294 ExprResult TemplateInstantiator::TransformCXXDefaultArgExpr(
1295 CXXDefaultArgExpr *E) {
1296 assert(!cast<FunctionDecl>(E->getParam()->getDeclContext())->
1297 getDescribedFunctionTemplate() &&
1298 "Default arg expressions are never formed in dependent cases.");
1299 return SemaRef.BuildCXXDefaultArgExpr(E->getUsedLocation(),
1300 cast<FunctionDecl>(E->getParam()->getDeclContext()),
1301 E->getParam());
1302 }
1303
1304 template<typename Fn>
TransformFunctionProtoType(TypeLocBuilder & TLB,FunctionProtoTypeLoc TL,CXXRecordDecl * ThisContext,unsigned ThisTypeQuals,Fn TransformExceptionSpec)1305 QualType TemplateInstantiator::TransformFunctionProtoType(TypeLocBuilder &TLB,
1306 FunctionProtoTypeLoc TL,
1307 CXXRecordDecl *ThisContext,
1308 unsigned ThisTypeQuals,
1309 Fn TransformExceptionSpec) {
1310 // We need a local instantiation scope for this function prototype.
1311 LocalInstantiationScope Scope(SemaRef, /*CombineWithOuterScope=*/true);
1312 return inherited::TransformFunctionProtoType(
1313 TLB, TL, ThisContext, ThisTypeQuals, TransformExceptionSpec);
1314 }
1315
1316 ParmVarDecl *
TransformFunctionTypeParam(ParmVarDecl * OldParm,int indexAdjustment,Optional<unsigned> NumExpansions,bool ExpectParameterPack)1317 TemplateInstantiator::TransformFunctionTypeParam(ParmVarDecl *OldParm,
1318 int indexAdjustment,
1319 Optional<unsigned> NumExpansions,
1320 bool ExpectParameterPack) {
1321 return SemaRef.SubstParmVarDecl(OldParm, TemplateArgs, indexAdjustment,
1322 NumExpansions, ExpectParameterPack);
1323 }
1324
1325 QualType
TransformTemplateTypeParmType(TypeLocBuilder & TLB,TemplateTypeParmTypeLoc TL)1326 TemplateInstantiator::TransformTemplateTypeParmType(TypeLocBuilder &TLB,
1327 TemplateTypeParmTypeLoc TL) {
1328 const TemplateTypeParmType *T = TL.getTypePtr();
1329 if (T->getDepth() < TemplateArgs.getNumLevels()) {
1330 // Replace the template type parameter with its corresponding
1331 // template argument.
1332
1333 // If the corresponding template argument is NULL or doesn't exist, it's
1334 // because we are performing instantiation from explicitly-specified
1335 // template arguments in a function template class, but there were some
1336 // arguments left unspecified.
1337 if (!TemplateArgs.hasTemplateArgument(T->getDepth(), T->getIndex())) {
1338 TemplateTypeParmTypeLoc NewTL
1339 = TLB.push<TemplateTypeParmTypeLoc>(TL.getType());
1340 NewTL.setNameLoc(TL.getNameLoc());
1341 return TL.getType();
1342 }
1343
1344 TemplateArgument Arg = TemplateArgs(T->getDepth(), T->getIndex());
1345
1346 if (T->isParameterPack()) {
1347 assert(Arg.getKind() == TemplateArgument::Pack &&
1348 "Missing argument pack");
1349
1350 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1351 // We have the template argument pack, but we're not expanding the
1352 // enclosing pack expansion yet. Just save the template argument
1353 // pack for later substitution.
1354 QualType Result
1355 = getSema().Context.getSubstTemplateTypeParmPackType(T, Arg);
1356 SubstTemplateTypeParmPackTypeLoc NewTL
1357 = TLB.push<SubstTemplateTypeParmPackTypeLoc>(Result);
1358 NewTL.setNameLoc(TL.getNameLoc());
1359 return Result;
1360 }
1361
1362 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1363 }
1364
1365 assert(Arg.getKind() == TemplateArgument::Type &&
1366 "Template argument kind mismatch");
1367
1368 QualType Replacement = Arg.getAsType();
1369
1370 // TODO: only do this uniquing once, at the start of instantiation.
1371 QualType Result
1372 = getSema().Context.getSubstTemplateTypeParmType(T, Replacement);
1373 SubstTemplateTypeParmTypeLoc NewTL
1374 = TLB.push<SubstTemplateTypeParmTypeLoc>(Result);
1375 NewTL.setNameLoc(TL.getNameLoc());
1376 return Result;
1377 }
1378
1379 // The template type parameter comes from an inner template (e.g.,
1380 // the template parameter list of a member template inside the
1381 // template we are instantiating). Create a new template type
1382 // parameter with the template "level" reduced by one.
1383 TemplateTypeParmDecl *NewTTPDecl = nullptr;
1384 if (TemplateTypeParmDecl *OldTTPDecl = T->getDecl())
1385 NewTTPDecl = cast_or_null<TemplateTypeParmDecl>(
1386 TransformDecl(TL.getNameLoc(), OldTTPDecl));
1387
1388 QualType Result
1389 = getSema().Context.getTemplateTypeParmType(T->getDepth()
1390 - TemplateArgs.getNumLevels(),
1391 T->getIndex(),
1392 T->isParameterPack(),
1393 NewTTPDecl);
1394 TemplateTypeParmTypeLoc NewTL = TLB.push<TemplateTypeParmTypeLoc>(Result);
1395 NewTL.setNameLoc(TL.getNameLoc());
1396 return Result;
1397 }
1398
1399 QualType
TransformSubstTemplateTypeParmPackType(TypeLocBuilder & TLB,SubstTemplateTypeParmPackTypeLoc TL)1400 TemplateInstantiator::TransformSubstTemplateTypeParmPackType(
1401 TypeLocBuilder &TLB,
1402 SubstTemplateTypeParmPackTypeLoc TL) {
1403 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1404 // We aren't expanding the parameter pack, so just return ourselves.
1405 SubstTemplateTypeParmPackTypeLoc NewTL
1406 = TLB.push<SubstTemplateTypeParmPackTypeLoc>(TL.getType());
1407 NewTL.setNameLoc(TL.getNameLoc());
1408 return TL.getType();
1409 }
1410
1411 TemplateArgument Arg = TL.getTypePtr()->getArgumentPack();
1412 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1413 QualType Result = Arg.getAsType();
1414
1415 Result = getSema().Context.getSubstTemplateTypeParmType(
1416 TL.getTypePtr()->getReplacedParameter(),
1417 Result);
1418 SubstTemplateTypeParmTypeLoc NewTL
1419 = TLB.push<SubstTemplateTypeParmTypeLoc>(Result);
1420 NewTL.setNameLoc(TL.getNameLoc());
1421 return Result;
1422 }
1423
1424 /// \brief Perform substitution on the type T with a given set of template
1425 /// arguments.
1426 ///
1427 /// This routine substitutes the given template arguments into the
1428 /// type T and produces the instantiated type.
1429 ///
1430 /// \param T the type into which the template arguments will be
1431 /// substituted. If this type is not dependent, it will be returned
1432 /// immediately.
1433 ///
1434 /// \param Args the template arguments that will be
1435 /// substituted for the top-level template parameters within T.
1436 ///
1437 /// \param Loc the location in the source code where this substitution
1438 /// is being performed. It will typically be the location of the
1439 /// declarator (if we're instantiating the type of some declaration)
1440 /// or the location of the type in the source code (if, e.g., we're
1441 /// instantiating the type of a cast expression).
1442 ///
1443 /// \param Entity the name of the entity associated with a declaration
1444 /// being instantiated (if any). May be empty to indicate that there
1445 /// is no such entity (if, e.g., this is a type that occurs as part of
1446 /// a cast expression) or that the entity has no name (e.g., an
1447 /// unnamed function parameter).
1448 ///
1449 /// \returns If the instantiation succeeds, the instantiated
1450 /// type. Otherwise, produces diagnostics and returns a NULL type.
SubstType(TypeSourceInfo * T,const MultiLevelTemplateArgumentList & Args,SourceLocation Loc,DeclarationName Entity)1451 TypeSourceInfo *Sema::SubstType(TypeSourceInfo *T,
1452 const MultiLevelTemplateArgumentList &Args,
1453 SourceLocation Loc,
1454 DeclarationName Entity) {
1455 assert(!ActiveTemplateInstantiations.empty() &&
1456 "Cannot perform an instantiation without some context on the "
1457 "instantiation stack");
1458
1459 if (!T->getType()->isInstantiationDependentType() &&
1460 !T->getType()->isVariablyModifiedType())
1461 return T;
1462
1463 TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
1464 return Instantiator.TransformType(T);
1465 }
1466
SubstType(TypeLoc TL,const MultiLevelTemplateArgumentList & Args,SourceLocation Loc,DeclarationName Entity)1467 TypeSourceInfo *Sema::SubstType(TypeLoc TL,
1468 const MultiLevelTemplateArgumentList &Args,
1469 SourceLocation Loc,
1470 DeclarationName Entity) {
1471 assert(!ActiveTemplateInstantiations.empty() &&
1472 "Cannot perform an instantiation without some context on the "
1473 "instantiation stack");
1474
1475 if (TL.getType().isNull())
1476 return nullptr;
1477
1478 if (!TL.getType()->isInstantiationDependentType() &&
1479 !TL.getType()->isVariablyModifiedType()) {
1480 // FIXME: Make a copy of the TypeLoc data here, so that we can
1481 // return a new TypeSourceInfo. Inefficient!
1482 TypeLocBuilder TLB;
1483 TLB.pushFullCopy(TL);
1484 return TLB.getTypeSourceInfo(Context, TL.getType());
1485 }
1486
1487 TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
1488 TypeLocBuilder TLB;
1489 TLB.reserve(TL.getFullDataSize());
1490 QualType Result = Instantiator.TransformType(TLB, TL);
1491 if (Result.isNull())
1492 return nullptr;
1493
1494 return TLB.getTypeSourceInfo(Context, Result);
1495 }
1496
1497 /// Deprecated form of the above.
SubstType(QualType T,const MultiLevelTemplateArgumentList & TemplateArgs,SourceLocation Loc,DeclarationName Entity)1498 QualType Sema::SubstType(QualType T,
1499 const MultiLevelTemplateArgumentList &TemplateArgs,
1500 SourceLocation Loc, DeclarationName Entity) {
1501 assert(!ActiveTemplateInstantiations.empty() &&
1502 "Cannot perform an instantiation without some context on the "
1503 "instantiation stack");
1504
1505 // If T is not a dependent type or a variably-modified type, there
1506 // is nothing to do.
1507 if (!T->isInstantiationDependentType() && !T->isVariablyModifiedType())
1508 return T;
1509
1510 TemplateInstantiator Instantiator(*this, TemplateArgs, Loc, Entity);
1511 return Instantiator.TransformType(T);
1512 }
1513
NeedsInstantiationAsFunctionType(TypeSourceInfo * T)1514 static bool NeedsInstantiationAsFunctionType(TypeSourceInfo *T) {
1515 if (T->getType()->isInstantiationDependentType() ||
1516 T->getType()->isVariablyModifiedType())
1517 return true;
1518
1519 TypeLoc TL = T->getTypeLoc().IgnoreParens();
1520 if (!TL.getAs<FunctionProtoTypeLoc>())
1521 return false;
1522
1523 FunctionProtoTypeLoc FP = TL.castAs<FunctionProtoTypeLoc>();
1524 for (unsigned I = 0, E = FP.getNumParams(); I != E; ++I) {
1525 ParmVarDecl *P = FP.getParam(I);
1526
1527 // This must be synthesized from a typedef.
1528 if (!P) continue;
1529
1530 // The parameter's type as written might be dependent even if the
1531 // decayed type was not dependent.
1532 if (TypeSourceInfo *TSInfo = P->getTypeSourceInfo())
1533 if (TSInfo->getType()->isInstantiationDependentType())
1534 return true;
1535
1536 // TODO: currently we always rebuild expressions. When we
1537 // properly get lazier about this, we should use the same
1538 // logic to avoid rebuilding prototypes here.
1539 if (P->hasDefaultArg())
1540 return true;
1541 }
1542
1543 return false;
1544 }
1545
1546 /// A form of SubstType intended specifically for instantiating the
1547 /// type of a FunctionDecl. Its purpose is solely to force the
1548 /// instantiation of default-argument expressions and to avoid
1549 /// instantiating an exception-specification.
SubstFunctionDeclType(TypeSourceInfo * T,const MultiLevelTemplateArgumentList & Args,SourceLocation Loc,DeclarationName Entity,CXXRecordDecl * ThisContext,unsigned ThisTypeQuals)1550 TypeSourceInfo *Sema::SubstFunctionDeclType(TypeSourceInfo *T,
1551 const MultiLevelTemplateArgumentList &Args,
1552 SourceLocation Loc,
1553 DeclarationName Entity,
1554 CXXRecordDecl *ThisContext,
1555 unsigned ThisTypeQuals) {
1556 assert(!ActiveTemplateInstantiations.empty() &&
1557 "Cannot perform an instantiation without some context on the "
1558 "instantiation stack");
1559
1560 if (!NeedsInstantiationAsFunctionType(T))
1561 return T;
1562
1563 TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
1564
1565 TypeLocBuilder TLB;
1566
1567 TypeLoc TL = T->getTypeLoc();
1568 TLB.reserve(TL.getFullDataSize());
1569
1570 QualType Result;
1571
1572 if (FunctionProtoTypeLoc Proto =
1573 TL.IgnoreParens().getAs<FunctionProtoTypeLoc>()) {
1574 // Instantiate the type, other than its exception specification. The
1575 // exception specification is instantiated in InitFunctionInstantiation
1576 // once we've built the FunctionDecl.
1577 // FIXME: Set the exception specification to EST_Uninstantiated here,
1578 // instead of rebuilding the function type again later.
1579 Result = Instantiator.TransformFunctionProtoType(
1580 TLB, Proto, ThisContext, ThisTypeQuals,
1581 [](FunctionProtoType::ExceptionSpecInfo &ESI,
1582 bool &Changed) { return false; });
1583 } else {
1584 Result = Instantiator.TransformType(TLB, TL);
1585 }
1586 if (Result.isNull())
1587 return nullptr;
1588
1589 return TLB.getTypeSourceInfo(Context, Result);
1590 }
1591
SubstExceptionSpec(FunctionDecl * New,const FunctionProtoType * Proto,const MultiLevelTemplateArgumentList & Args)1592 void Sema::SubstExceptionSpec(FunctionDecl *New, const FunctionProtoType *Proto,
1593 const MultiLevelTemplateArgumentList &Args) {
1594 FunctionProtoType::ExceptionSpecInfo ESI =
1595 Proto->getExtProtoInfo().ExceptionSpec;
1596 assert(ESI.Type != EST_Uninstantiated);
1597
1598 TemplateInstantiator Instantiator(*this, Args, New->getLocation(),
1599 New->getDeclName());
1600
1601 SmallVector<QualType, 4> ExceptionStorage;
1602 bool Changed = false;
1603 if (Instantiator.TransformExceptionSpec(
1604 New->getTypeSourceInfo()->getTypeLoc().getLocEnd(), ESI,
1605 ExceptionStorage, Changed))
1606 // On error, recover by dropping the exception specification.
1607 ESI.Type = EST_None;
1608
1609 UpdateExceptionSpec(New, ESI);
1610 }
1611
SubstParmVarDecl(ParmVarDecl * OldParm,const MultiLevelTemplateArgumentList & TemplateArgs,int indexAdjustment,Optional<unsigned> NumExpansions,bool ExpectParameterPack)1612 ParmVarDecl *Sema::SubstParmVarDecl(ParmVarDecl *OldParm,
1613 const MultiLevelTemplateArgumentList &TemplateArgs,
1614 int indexAdjustment,
1615 Optional<unsigned> NumExpansions,
1616 bool ExpectParameterPack) {
1617 TypeSourceInfo *OldDI = OldParm->getTypeSourceInfo();
1618 TypeSourceInfo *NewDI = nullptr;
1619
1620 TypeLoc OldTL = OldDI->getTypeLoc();
1621 if (PackExpansionTypeLoc ExpansionTL = OldTL.getAs<PackExpansionTypeLoc>()) {
1622
1623 // We have a function parameter pack. Substitute into the pattern of the
1624 // expansion.
1625 NewDI = SubstType(ExpansionTL.getPatternLoc(), TemplateArgs,
1626 OldParm->getLocation(), OldParm->getDeclName());
1627 if (!NewDI)
1628 return nullptr;
1629
1630 if (NewDI->getType()->containsUnexpandedParameterPack()) {
1631 // We still have unexpanded parameter packs, which means that
1632 // our function parameter is still a function parameter pack.
1633 // Therefore, make its type a pack expansion type.
1634 NewDI = CheckPackExpansion(NewDI, ExpansionTL.getEllipsisLoc(),
1635 NumExpansions);
1636 } else if (ExpectParameterPack) {
1637 // We expected to get a parameter pack but didn't (because the type
1638 // itself is not a pack expansion type), so complain. This can occur when
1639 // the substitution goes through an alias template that "loses" the
1640 // pack expansion.
1641 Diag(OldParm->getLocation(),
1642 diag::err_function_parameter_pack_without_parameter_packs)
1643 << NewDI->getType();
1644 return nullptr;
1645 }
1646 } else {
1647 NewDI = SubstType(OldDI, TemplateArgs, OldParm->getLocation(),
1648 OldParm->getDeclName());
1649 }
1650
1651 if (!NewDI)
1652 return nullptr;
1653
1654 if (NewDI->getType()->isVoidType()) {
1655 Diag(OldParm->getLocation(), diag::err_param_with_void_type);
1656 return nullptr;
1657 }
1658
1659 ParmVarDecl *NewParm = CheckParameter(Context.getTranslationUnitDecl(),
1660 OldParm->getInnerLocStart(),
1661 OldParm->getLocation(),
1662 OldParm->getIdentifier(),
1663 NewDI->getType(), NewDI,
1664 OldParm->getStorageClass());
1665 if (!NewParm)
1666 return nullptr;
1667
1668 // Mark the (new) default argument as uninstantiated (if any).
1669 if (OldParm->hasUninstantiatedDefaultArg()) {
1670 Expr *Arg = OldParm->getUninstantiatedDefaultArg();
1671 NewParm->setUninstantiatedDefaultArg(Arg);
1672 } else if (OldParm->hasUnparsedDefaultArg()) {
1673 NewParm->setUnparsedDefaultArg();
1674 UnparsedDefaultArgInstantiations[OldParm].push_back(NewParm);
1675 } else if (Expr *Arg = OldParm->getDefaultArg()) {
1676 FunctionDecl *OwningFunc = cast<FunctionDecl>(OldParm->getDeclContext());
1677 if (OwningFunc->isLexicallyWithinFunctionOrMethod()) {
1678 // Instantiate default arguments for methods of local classes (DR1484)
1679 // and non-defining declarations.
1680 Sema::ContextRAII SavedContext(*this, OwningFunc);
1681 LocalInstantiationScope Local(*this);
1682 ExprResult NewArg = SubstExpr(Arg, TemplateArgs);
1683 if (NewArg.isUsable()) {
1684 // It would be nice if we still had this.
1685 SourceLocation EqualLoc = NewArg.get()->getLocStart();
1686 SetParamDefaultArgument(NewParm, NewArg.get(), EqualLoc);
1687 }
1688 } else {
1689 // FIXME: if we non-lazily instantiated non-dependent default args for
1690 // non-dependent parameter types we could remove a bunch of duplicate
1691 // conversion warnings for such arguments.
1692 NewParm->setUninstantiatedDefaultArg(Arg);
1693 }
1694 }
1695
1696 NewParm->setHasInheritedDefaultArg(OldParm->hasInheritedDefaultArg());
1697
1698 if (OldParm->isParameterPack() && !NewParm->isParameterPack()) {
1699 // Add the new parameter to the instantiated parameter pack.
1700 CurrentInstantiationScope->InstantiatedLocalPackArg(OldParm, NewParm);
1701 } else {
1702 // Introduce an Old -> New mapping
1703 CurrentInstantiationScope->InstantiatedLocal(OldParm, NewParm);
1704 }
1705
1706 // FIXME: OldParm may come from a FunctionProtoType, in which case CurContext
1707 // can be anything, is this right ?
1708 NewParm->setDeclContext(CurContext);
1709
1710 NewParm->setScopeInfo(OldParm->getFunctionScopeDepth(),
1711 OldParm->getFunctionScopeIndex() + indexAdjustment);
1712
1713 InstantiateAttrs(TemplateArgs, OldParm, NewParm);
1714
1715 return NewParm;
1716 }
1717
1718 /// \brief Substitute the given template arguments into the given set of
1719 /// parameters, producing the set of parameter types that would be generated
1720 /// from such a substitution.
SubstParmTypes(SourceLocation Loc,ParmVarDecl ** Params,unsigned NumParams,const MultiLevelTemplateArgumentList & TemplateArgs,SmallVectorImpl<QualType> & ParamTypes,SmallVectorImpl<ParmVarDecl * > * OutParams)1721 bool Sema::SubstParmTypes(SourceLocation Loc,
1722 ParmVarDecl **Params, unsigned NumParams,
1723 const MultiLevelTemplateArgumentList &TemplateArgs,
1724 SmallVectorImpl<QualType> &ParamTypes,
1725 SmallVectorImpl<ParmVarDecl *> *OutParams) {
1726 assert(!ActiveTemplateInstantiations.empty() &&
1727 "Cannot perform an instantiation without some context on the "
1728 "instantiation stack");
1729
1730 TemplateInstantiator Instantiator(*this, TemplateArgs, Loc,
1731 DeclarationName());
1732 return Instantiator.TransformFunctionTypeParams(Loc, Params, NumParams,
1733 nullptr, ParamTypes,
1734 OutParams);
1735 }
1736
1737 /// \brief Perform substitution on the base class specifiers of the
1738 /// given class template specialization.
1739 ///
1740 /// Produces a diagnostic and returns true on error, returns false and
1741 /// attaches the instantiated base classes to the class template
1742 /// specialization if successful.
1743 bool
SubstBaseSpecifiers(CXXRecordDecl * Instantiation,CXXRecordDecl * Pattern,const MultiLevelTemplateArgumentList & TemplateArgs)1744 Sema::SubstBaseSpecifiers(CXXRecordDecl *Instantiation,
1745 CXXRecordDecl *Pattern,
1746 const MultiLevelTemplateArgumentList &TemplateArgs) {
1747 bool Invalid = false;
1748 SmallVector<CXXBaseSpecifier*, 4> InstantiatedBases;
1749 for (const auto &Base : Pattern->bases()) {
1750 if (!Base.getType()->isDependentType()) {
1751 if (const CXXRecordDecl *RD = Base.getType()->getAsCXXRecordDecl()) {
1752 if (RD->isInvalidDecl())
1753 Instantiation->setInvalidDecl();
1754 }
1755 InstantiatedBases.push_back(new (Context) CXXBaseSpecifier(Base));
1756 continue;
1757 }
1758
1759 SourceLocation EllipsisLoc;
1760 TypeSourceInfo *BaseTypeLoc;
1761 if (Base.isPackExpansion()) {
1762 // This is a pack expansion. See whether we should expand it now, or
1763 // wait until later.
1764 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
1765 collectUnexpandedParameterPacks(Base.getTypeSourceInfo()->getTypeLoc(),
1766 Unexpanded);
1767 bool ShouldExpand = false;
1768 bool RetainExpansion = false;
1769 Optional<unsigned> NumExpansions;
1770 if (CheckParameterPacksForExpansion(Base.getEllipsisLoc(),
1771 Base.getSourceRange(),
1772 Unexpanded,
1773 TemplateArgs, ShouldExpand,
1774 RetainExpansion,
1775 NumExpansions)) {
1776 Invalid = true;
1777 continue;
1778 }
1779
1780 // If we should expand this pack expansion now, do so.
1781 if (ShouldExpand) {
1782 for (unsigned I = 0; I != *NumExpansions; ++I) {
1783 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, I);
1784
1785 TypeSourceInfo *BaseTypeLoc = SubstType(Base.getTypeSourceInfo(),
1786 TemplateArgs,
1787 Base.getSourceRange().getBegin(),
1788 DeclarationName());
1789 if (!BaseTypeLoc) {
1790 Invalid = true;
1791 continue;
1792 }
1793
1794 if (CXXBaseSpecifier *InstantiatedBase
1795 = CheckBaseSpecifier(Instantiation,
1796 Base.getSourceRange(),
1797 Base.isVirtual(),
1798 Base.getAccessSpecifierAsWritten(),
1799 BaseTypeLoc,
1800 SourceLocation()))
1801 InstantiatedBases.push_back(InstantiatedBase);
1802 else
1803 Invalid = true;
1804 }
1805
1806 continue;
1807 }
1808
1809 // The resulting base specifier will (still) be a pack expansion.
1810 EllipsisLoc = Base.getEllipsisLoc();
1811 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, -1);
1812 BaseTypeLoc = SubstType(Base.getTypeSourceInfo(),
1813 TemplateArgs,
1814 Base.getSourceRange().getBegin(),
1815 DeclarationName());
1816 } else {
1817 BaseTypeLoc = SubstType(Base.getTypeSourceInfo(),
1818 TemplateArgs,
1819 Base.getSourceRange().getBegin(),
1820 DeclarationName());
1821 }
1822
1823 if (!BaseTypeLoc) {
1824 Invalid = true;
1825 continue;
1826 }
1827
1828 if (CXXBaseSpecifier *InstantiatedBase
1829 = CheckBaseSpecifier(Instantiation,
1830 Base.getSourceRange(),
1831 Base.isVirtual(),
1832 Base.getAccessSpecifierAsWritten(),
1833 BaseTypeLoc,
1834 EllipsisLoc))
1835 InstantiatedBases.push_back(InstantiatedBase);
1836 else
1837 Invalid = true;
1838 }
1839
1840 if (!Invalid &&
1841 AttachBaseSpecifiers(Instantiation, InstantiatedBases.data(),
1842 InstantiatedBases.size()))
1843 Invalid = true;
1844
1845 return Invalid;
1846 }
1847
1848 // Defined via #include from SemaTemplateInstantiateDecl.cpp
1849 namespace clang {
1850 namespace sema {
1851 Attr *instantiateTemplateAttribute(const Attr *At, ASTContext &C, Sema &S,
1852 const MultiLevelTemplateArgumentList &TemplateArgs);
1853 }
1854 }
1855
1856 /// Determine whether we would be unable to instantiate this template (because
1857 /// it either has no definition, or is in the process of being instantiated).
DiagnoseUninstantiableTemplate(Sema & S,SourceLocation PointOfInstantiation,TagDecl * Instantiation,bool InstantiatedFromMember,TagDecl * Pattern,TagDecl * PatternDef,TemplateSpecializationKind TSK,bool Complain=true)1858 static bool DiagnoseUninstantiableTemplate(Sema &S,
1859 SourceLocation PointOfInstantiation,
1860 TagDecl *Instantiation,
1861 bool InstantiatedFromMember,
1862 TagDecl *Pattern,
1863 TagDecl *PatternDef,
1864 TemplateSpecializationKind TSK,
1865 bool Complain = true) {
1866 if (PatternDef && !PatternDef->isBeingDefined())
1867 return false;
1868
1869 if (!Complain || (PatternDef && PatternDef->isInvalidDecl())) {
1870 // Say nothing
1871 } else if (PatternDef) {
1872 assert(PatternDef->isBeingDefined());
1873 S.Diag(PointOfInstantiation,
1874 diag::err_template_instantiate_within_definition)
1875 << (TSK != TSK_ImplicitInstantiation)
1876 << S.Context.getTypeDeclType(Instantiation);
1877 // Not much point in noting the template declaration here, since
1878 // we're lexically inside it.
1879 Instantiation->setInvalidDecl();
1880 } else if (InstantiatedFromMember) {
1881 S.Diag(PointOfInstantiation,
1882 diag::err_implicit_instantiate_member_undefined)
1883 << S.Context.getTypeDeclType(Instantiation);
1884 S.Diag(Pattern->getLocation(), diag::note_member_declared_at);
1885 } else {
1886 S.Diag(PointOfInstantiation, diag::err_template_instantiate_undefined)
1887 << (TSK != TSK_ImplicitInstantiation)
1888 << S.Context.getTypeDeclType(Instantiation);
1889 S.Diag(Pattern->getLocation(), diag::note_template_decl_here);
1890 }
1891
1892 // In general, Instantiation isn't marked invalid to get more than one
1893 // error for multiple undefined instantiations. But the code that does
1894 // explicit declaration -> explicit definition conversion can't handle
1895 // invalid declarations, so mark as invalid in that case.
1896 if (TSK == TSK_ExplicitInstantiationDeclaration)
1897 Instantiation->setInvalidDecl();
1898 return true;
1899 }
1900
1901 /// \brief Instantiate the definition of a class from a given pattern.
1902 ///
1903 /// \param PointOfInstantiation The point of instantiation within the
1904 /// source code.
1905 ///
1906 /// \param Instantiation is the declaration whose definition is being
1907 /// instantiated. This will be either a class template specialization
1908 /// or a member class of a class template specialization.
1909 ///
1910 /// \param Pattern is the pattern from which the instantiation
1911 /// occurs. This will be either the declaration of a class template or
1912 /// the declaration of a member class of a class template.
1913 ///
1914 /// \param TemplateArgs The template arguments to be substituted into
1915 /// the pattern.
1916 ///
1917 /// \param TSK the kind of implicit or explicit instantiation to perform.
1918 ///
1919 /// \param Complain whether to complain if the class cannot be instantiated due
1920 /// to the lack of a definition.
1921 ///
1922 /// \returns true if an error occurred, false otherwise.
1923 bool
InstantiateClass(SourceLocation PointOfInstantiation,CXXRecordDecl * Instantiation,CXXRecordDecl * Pattern,const MultiLevelTemplateArgumentList & TemplateArgs,TemplateSpecializationKind TSK,bool Complain)1924 Sema::InstantiateClass(SourceLocation PointOfInstantiation,
1925 CXXRecordDecl *Instantiation, CXXRecordDecl *Pattern,
1926 const MultiLevelTemplateArgumentList &TemplateArgs,
1927 TemplateSpecializationKind TSK,
1928 bool Complain) {
1929 CXXRecordDecl *PatternDef
1930 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition());
1931 if (DiagnoseUninstantiableTemplate(*this, PointOfInstantiation, Instantiation,
1932 Instantiation->getInstantiatedFromMemberClass(),
1933 Pattern, PatternDef, TSK, Complain))
1934 return true;
1935 Pattern = PatternDef;
1936
1937 // \brief Record the point of instantiation.
1938 if (MemberSpecializationInfo *MSInfo
1939 = Instantiation->getMemberSpecializationInfo()) {
1940 MSInfo->setTemplateSpecializationKind(TSK);
1941 MSInfo->setPointOfInstantiation(PointOfInstantiation);
1942 } else if (ClassTemplateSpecializationDecl *Spec
1943 = dyn_cast<ClassTemplateSpecializationDecl>(Instantiation)) {
1944 Spec->setTemplateSpecializationKind(TSK);
1945 Spec->setPointOfInstantiation(PointOfInstantiation);
1946 }
1947
1948 InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
1949 if (Inst.isInvalid())
1950 return true;
1951
1952 // Enter the scope of this instantiation. We don't use
1953 // PushDeclContext because we don't have a scope.
1954 ContextRAII SavedContext(*this, Instantiation);
1955 EnterExpressionEvaluationContext EvalContext(*this,
1956 Sema::PotentiallyEvaluated);
1957
1958 // If this is an instantiation of a local class, merge this local
1959 // instantiation scope with the enclosing scope. Otherwise, every
1960 // instantiation of a class has its own local instantiation scope.
1961 bool MergeWithParentScope = !Instantiation->isDefinedOutsideFunctionOrMethod();
1962 LocalInstantiationScope Scope(*this, MergeWithParentScope);
1963
1964 // Pull attributes from the pattern onto the instantiation.
1965 InstantiateAttrs(TemplateArgs, Pattern, Instantiation);
1966
1967 // Start the definition of this instantiation.
1968 Instantiation->startDefinition();
1969
1970 // The instantiation is visible here, even if it was first declared in an
1971 // unimported module.
1972 Instantiation->setHidden(false);
1973
1974 // FIXME: This loses the as-written tag kind for an explicit instantiation.
1975 Instantiation->setTagKind(Pattern->getTagKind());
1976
1977 // Do substitution on the base class specifiers.
1978 if (SubstBaseSpecifiers(Instantiation, Pattern, TemplateArgs))
1979 Instantiation->setInvalidDecl();
1980
1981 TemplateDeclInstantiator Instantiator(*this, Instantiation, TemplateArgs);
1982 SmallVector<Decl*, 4> Fields;
1983 // Delay instantiation of late parsed attributes.
1984 LateInstantiatedAttrVec LateAttrs;
1985 Instantiator.enableLateAttributeInstantiation(&LateAttrs);
1986
1987 for (auto *Member : Pattern->decls()) {
1988 // Don't instantiate members not belonging in this semantic context.
1989 // e.g. for:
1990 // @code
1991 // template <int i> class A {
1992 // class B *g;
1993 // };
1994 // @endcode
1995 // 'class B' has the template as lexical context but semantically it is
1996 // introduced in namespace scope.
1997 if (Member->getDeclContext() != Pattern)
1998 continue;
1999
2000 if (Member->isInvalidDecl()) {
2001 Instantiation->setInvalidDecl();
2002 continue;
2003 }
2004
2005 Decl *NewMember = Instantiator.Visit(Member);
2006 if (NewMember) {
2007 if (FieldDecl *Field = dyn_cast<FieldDecl>(NewMember)) {
2008 Fields.push_back(Field);
2009 } else if (EnumDecl *Enum = dyn_cast<EnumDecl>(NewMember)) {
2010 // C++11 [temp.inst]p1: The implicit instantiation of a class template
2011 // specialization causes the implicit instantiation of the definitions
2012 // of unscoped member enumerations.
2013 // Record a point of instantiation for this implicit instantiation.
2014 if (TSK == TSK_ImplicitInstantiation && !Enum->isScoped() &&
2015 Enum->isCompleteDefinition()) {
2016 MemberSpecializationInfo *MSInfo =Enum->getMemberSpecializationInfo();
2017 assert(MSInfo && "no spec info for member enum specialization");
2018 MSInfo->setTemplateSpecializationKind(TSK_ImplicitInstantiation);
2019 MSInfo->setPointOfInstantiation(PointOfInstantiation);
2020 }
2021 } else if (StaticAssertDecl *SA = dyn_cast<StaticAssertDecl>(NewMember)) {
2022 if (SA->isFailed()) {
2023 // A static_assert failed. Bail out; instantiating this
2024 // class is probably not meaningful.
2025 Instantiation->setInvalidDecl();
2026 break;
2027 }
2028 }
2029
2030 if (NewMember->isInvalidDecl())
2031 Instantiation->setInvalidDecl();
2032 } else {
2033 // FIXME: Eventually, a NULL return will mean that one of the
2034 // instantiations was a semantic disaster, and we'll want to mark the
2035 // declaration invalid.
2036 // For now, we expect to skip some members that we can't yet handle.
2037 }
2038 }
2039
2040 // Finish checking fields.
2041 ActOnFields(nullptr, Instantiation->getLocation(), Instantiation, Fields,
2042 SourceLocation(), SourceLocation(), nullptr);
2043 CheckCompletedCXXClass(Instantiation);
2044
2045 // Default arguments are parsed, if not instantiated. We can go instantiate
2046 // default arg exprs for default constructors if necessary now.
2047 ActOnFinishCXXNonNestedClass(Instantiation);
2048
2049 // Instantiate late parsed attributes, and attach them to their decls.
2050 // See Sema::InstantiateAttrs
2051 for (LateInstantiatedAttrVec::iterator I = LateAttrs.begin(),
2052 E = LateAttrs.end(); I != E; ++I) {
2053 assert(CurrentInstantiationScope == Instantiator.getStartingScope());
2054 CurrentInstantiationScope = I->Scope;
2055
2056 // Allow 'this' within late-parsed attributes.
2057 NamedDecl *ND = dyn_cast<NamedDecl>(I->NewDecl);
2058 CXXRecordDecl *ThisContext =
2059 dyn_cast_or_null<CXXRecordDecl>(ND->getDeclContext());
2060 CXXThisScopeRAII ThisScope(*this, ThisContext, /*TypeQuals*/0,
2061 ND && ND->isCXXInstanceMember());
2062
2063 Attr *NewAttr =
2064 instantiateTemplateAttribute(I->TmplAttr, Context, *this, TemplateArgs);
2065 I->NewDecl->addAttr(NewAttr);
2066 LocalInstantiationScope::deleteScopes(I->Scope,
2067 Instantiator.getStartingScope());
2068 }
2069 Instantiator.disableLateAttributeInstantiation();
2070 LateAttrs.clear();
2071
2072 ActOnFinishDelayedMemberInitializers(Instantiation);
2073
2074 // FIXME: We should do something similar for explicit instantiations so they
2075 // end up in the right module.
2076 if (TSK == TSK_ImplicitInstantiation) {
2077 Instantiation->setLocation(Pattern->getLocation());
2078 Instantiation->setLocStart(Pattern->getInnerLocStart());
2079 Instantiation->setRBraceLoc(Pattern->getRBraceLoc());
2080 }
2081
2082 if (!Instantiation->isInvalidDecl()) {
2083 // Perform any dependent diagnostics from the pattern.
2084 PerformDependentDiagnostics(Pattern, TemplateArgs);
2085
2086 // Instantiate any out-of-line class template partial
2087 // specializations now.
2088 for (TemplateDeclInstantiator::delayed_partial_spec_iterator
2089 P = Instantiator.delayed_partial_spec_begin(),
2090 PEnd = Instantiator.delayed_partial_spec_end();
2091 P != PEnd; ++P) {
2092 if (!Instantiator.InstantiateClassTemplatePartialSpecialization(
2093 P->first, P->second)) {
2094 Instantiation->setInvalidDecl();
2095 break;
2096 }
2097 }
2098
2099 // Instantiate any out-of-line variable template partial
2100 // specializations now.
2101 for (TemplateDeclInstantiator::delayed_var_partial_spec_iterator
2102 P = Instantiator.delayed_var_partial_spec_begin(),
2103 PEnd = Instantiator.delayed_var_partial_spec_end();
2104 P != PEnd; ++P) {
2105 if (!Instantiator.InstantiateVarTemplatePartialSpecialization(
2106 P->first, P->second)) {
2107 Instantiation->setInvalidDecl();
2108 break;
2109 }
2110 }
2111 }
2112
2113 // Exit the scope of this instantiation.
2114 SavedContext.pop();
2115
2116 if (!Instantiation->isInvalidDecl()) {
2117 Consumer.HandleTagDeclDefinition(Instantiation);
2118
2119 // Always emit the vtable for an explicit instantiation definition
2120 // of a polymorphic class template specialization.
2121 if (TSK == TSK_ExplicitInstantiationDefinition)
2122 MarkVTableUsed(PointOfInstantiation, Instantiation, true);
2123 }
2124
2125 return Instantiation->isInvalidDecl();
2126 }
2127
2128 /// \brief Instantiate the definition of an enum from a given pattern.
2129 ///
2130 /// \param PointOfInstantiation The point of instantiation within the
2131 /// source code.
2132 /// \param Instantiation is the declaration whose definition is being
2133 /// instantiated. This will be a member enumeration of a class
2134 /// temploid specialization, or a local enumeration within a
2135 /// function temploid specialization.
2136 /// \param Pattern The templated declaration from which the instantiation
2137 /// occurs.
2138 /// \param TemplateArgs The template arguments to be substituted into
2139 /// the pattern.
2140 /// \param TSK The kind of implicit or explicit instantiation to perform.
2141 ///
2142 /// \return \c true if an error occurred, \c false otherwise.
InstantiateEnum(SourceLocation PointOfInstantiation,EnumDecl * Instantiation,EnumDecl * Pattern,const MultiLevelTemplateArgumentList & TemplateArgs,TemplateSpecializationKind TSK)2143 bool Sema::InstantiateEnum(SourceLocation PointOfInstantiation,
2144 EnumDecl *Instantiation, EnumDecl *Pattern,
2145 const MultiLevelTemplateArgumentList &TemplateArgs,
2146 TemplateSpecializationKind TSK) {
2147 EnumDecl *PatternDef = Pattern->getDefinition();
2148 if (DiagnoseUninstantiableTemplate(*this, PointOfInstantiation, Instantiation,
2149 Instantiation->getInstantiatedFromMemberEnum(),
2150 Pattern, PatternDef, TSK,/*Complain*/true))
2151 return true;
2152 Pattern = PatternDef;
2153
2154 // Record the point of instantiation.
2155 if (MemberSpecializationInfo *MSInfo
2156 = Instantiation->getMemberSpecializationInfo()) {
2157 MSInfo->setTemplateSpecializationKind(TSK);
2158 MSInfo->setPointOfInstantiation(PointOfInstantiation);
2159 }
2160
2161 InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
2162 if (Inst.isInvalid())
2163 return true;
2164
2165 // The instantiation is visible here, even if it was first declared in an
2166 // unimported module.
2167 Instantiation->setHidden(false);
2168
2169 // Enter the scope of this instantiation. We don't use
2170 // PushDeclContext because we don't have a scope.
2171 ContextRAII SavedContext(*this, Instantiation);
2172 EnterExpressionEvaluationContext EvalContext(*this,
2173 Sema::PotentiallyEvaluated);
2174
2175 LocalInstantiationScope Scope(*this, /*MergeWithParentScope*/true);
2176
2177 // Pull attributes from the pattern onto the instantiation.
2178 InstantiateAttrs(TemplateArgs, Pattern, Instantiation);
2179
2180 TemplateDeclInstantiator Instantiator(*this, Instantiation, TemplateArgs);
2181 Instantiator.InstantiateEnumDefinition(Instantiation, Pattern);
2182
2183 // Exit the scope of this instantiation.
2184 SavedContext.pop();
2185
2186 return Instantiation->isInvalidDecl();
2187 }
2188
2189
2190 /// \brief Instantiate the definition of a field from the given pattern.
2191 ///
2192 /// \param PointOfInstantiation The point of instantiation within the
2193 /// source code.
2194 /// \param Instantiation is the declaration whose definition is being
2195 /// instantiated. This will be a class of a class temploid
2196 /// specialization, or a local enumeration within a function temploid
2197 /// specialization.
2198 /// \param Pattern The templated declaration from which the instantiation
2199 /// occurs.
2200 /// \param TemplateArgs The template arguments to be substituted into
2201 /// the pattern.
2202 ///
2203 /// \return \c true if an error occurred, \c false otherwise.
InstantiateInClassInitializer(SourceLocation PointOfInstantiation,FieldDecl * Instantiation,FieldDecl * Pattern,const MultiLevelTemplateArgumentList & TemplateArgs)2204 bool Sema::InstantiateInClassInitializer(
2205 SourceLocation PointOfInstantiation, FieldDecl *Instantiation,
2206 FieldDecl *Pattern, const MultiLevelTemplateArgumentList &TemplateArgs) {
2207 // If there is no initializer, we don't need to do anything.
2208 if (!Pattern->hasInClassInitializer())
2209 return false;
2210
2211 assert(Instantiation->getInClassInitStyle() ==
2212 Pattern->getInClassInitStyle() &&
2213 "pattern and instantiation disagree about init style");
2214
2215 // Error out if we haven't parsed the initializer of the pattern yet because
2216 // we are waiting for the closing brace of the outer class.
2217 Expr *OldInit = Pattern->getInClassInitializer();
2218 if (!OldInit) {
2219 RecordDecl *PatternRD = Pattern->getParent();
2220 RecordDecl *OutermostClass = PatternRD->getOuterLexicalRecordContext();
2221 if (OutermostClass == PatternRD) {
2222 Diag(Pattern->getLocEnd(), diag::err_in_class_initializer_not_yet_parsed)
2223 << PatternRD << Pattern;
2224 } else {
2225 Diag(Pattern->getLocEnd(),
2226 diag::err_in_class_initializer_not_yet_parsed_outer_class)
2227 << PatternRD << OutermostClass << Pattern;
2228 }
2229 Instantiation->setInvalidDecl();
2230 return true;
2231 }
2232
2233 InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
2234 if (Inst.isInvalid())
2235 return true;
2236
2237 // Enter the scope of this instantiation. We don't use PushDeclContext because
2238 // we don't have a scope.
2239 ContextRAII SavedContext(*this, Instantiation->getParent());
2240 EnterExpressionEvaluationContext EvalContext(*this,
2241 Sema::PotentiallyEvaluated);
2242
2243 LocalInstantiationScope Scope(*this, true);
2244
2245 // Instantiate the initializer.
2246 ActOnStartCXXInClassMemberInitializer();
2247 CXXThisScopeRAII ThisScope(*this, Instantiation->getParent(), /*TypeQuals=*/0);
2248
2249 ExprResult NewInit = SubstInitializer(OldInit, TemplateArgs,
2250 /*CXXDirectInit=*/false);
2251 Expr *Init = NewInit.get();
2252 assert((!Init || !isa<ParenListExpr>(Init)) && "call-style init in class");
2253 ActOnFinishCXXInClassMemberInitializer(
2254 Instantiation, Init ? Init->getLocStart() : SourceLocation(), Init);
2255
2256 // Exit the scope of this instantiation.
2257 SavedContext.pop();
2258
2259 // Return true if the in-class initializer is still missing.
2260 return !Instantiation->getInClassInitializer();
2261 }
2262
2263 namespace {
2264 /// \brief A partial specialization whose template arguments have matched
2265 /// a given template-id.
2266 struct PartialSpecMatchResult {
2267 ClassTemplatePartialSpecializationDecl *Partial;
2268 TemplateArgumentList *Args;
2269 };
2270 }
2271
InstantiateClassTemplateSpecialization(SourceLocation PointOfInstantiation,ClassTemplateSpecializationDecl * ClassTemplateSpec,TemplateSpecializationKind TSK,bool Complain)2272 bool Sema::InstantiateClassTemplateSpecialization(
2273 SourceLocation PointOfInstantiation,
2274 ClassTemplateSpecializationDecl *ClassTemplateSpec,
2275 TemplateSpecializationKind TSK, bool Complain) {
2276 // Perform the actual instantiation on the canonical declaration.
2277 ClassTemplateSpec = cast<ClassTemplateSpecializationDecl>(
2278 ClassTemplateSpec->getCanonicalDecl());
2279 if (ClassTemplateSpec->isInvalidDecl())
2280 return true;
2281
2282 ClassTemplateDecl *Template = ClassTemplateSpec->getSpecializedTemplate();
2283 CXXRecordDecl *Pattern = nullptr;
2284
2285 // C++ [temp.class.spec.match]p1:
2286 // When a class template is used in a context that requires an
2287 // instantiation of the class, it is necessary to determine
2288 // whether the instantiation is to be generated using the primary
2289 // template or one of the partial specializations. This is done by
2290 // matching the template arguments of the class template
2291 // specialization with the template argument lists of the partial
2292 // specializations.
2293 typedef PartialSpecMatchResult MatchResult;
2294 SmallVector<MatchResult, 4> Matched;
2295 SmallVector<ClassTemplatePartialSpecializationDecl *, 4> PartialSpecs;
2296 Template->getPartialSpecializations(PartialSpecs);
2297 TemplateSpecCandidateSet FailedCandidates(PointOfInstantiation);
2298 for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I) {
2299 ClassTemplatePartialSpecializationDecl *Partial = PartialSpecs[I];
2300 TemplateDeductionInfo Info(FailedCandidates.getLocation());
2301 if (TemplateDeductionResult Result
2302 = DeduceTemplateArguments(Partial,
2303 ClassTemplateSpec->getTemplateArgs(),
2304 Info)) {
2305 // Store the failed-deduction information for use in diagnostics, later.
2306 // TODO: Actually use the failed-deduction info?
2307 FailedCandidates.addCandidate()
2308 .set(Partial, MakeDeductionFailureInfo(Context, Result, Info));
2309 (void)Result;
2310 } else {
2311 Matched.push_back(PartialSpecMatchResult());
2312 Matched.back().Partial = Partial;
2313 Matched.back().Args = Info.take();
2314 }
2315 }
2316
2317 // If we're dealing with a member template where the template parameters
2318 // have been instantiated, this provides the original template parameters
2319 // from which the member template's parameters were instantiated.
2320
2321 if (Matched.size() >= 1) {
2322 SmallVectorImpl<MatchResult>::iterator Best = Matched.begin();
2323 if (Matched.size() == 1) {
2324 // -- If exactly one matching specialization is found, the
2325 // instantiation is generated from that specialization.
2326 // We don't need to do anything for this.
2327 } else {
2328 // -- If more than one matching specialization is found, the
2329 // partial order rules (14.5.4.2) are used to determine
2330 // whether one of the specializations is more specialized
2331 // than the others. If none of the specializations is more
2332 // specialized than all of the other matching
2333 // specializations, then the use of the class template is
2334 // ambiguous and the program is ill-formed.
2335 for (SmallVectorImpl<MatchResult>::iterator P = Best + 1,
2336 PEnd = Matched.end();
2337 P != PEnd; ++P) {
2338 if (getMoreSpecializedPartialSpecialization(P->Partial, Best->Partial,
2339 PointOfInstantiation)
2340 == P->Partial)
2341 Best = P;
2342 }
2343
2344 // Determine if the best partial specialization is more specialized than
2345 // the others.
2346 bool Ambiguous = false;
2347 for (SmallVectorImpl<MatchResult>::iterator P = Matched.begin(),
2348 PEnd = Matched.end();
2349 P != PEnd; ++P) {
2350 if (P != Best &&
2351 getMoreSpecializedPartialSpecialization(P->Partial, Best->Partial,
2352 PointOfInstantiation)
2353 != Best->Partial) {
2354 Ambiguous = true;
2355 break;
2356 }
2357 }
2358
2359 if (Ambiguous) {
2360 // Partial ordering did not produce a clear winner. Complain.
2361 ClassTemplateSpec->setInvalidDecl();
2362 Diag(PointOfInstantiation, diag::err_partial_spec_ordering_ambiguous)
2363 << ClassTemplateSpec;
2364
2365 // Print the matching partial specializations.
2366 for (SmallVectorImpl<MatchResult>::iterator P = Matched.begin(),
2367 PEnd = Matched.end();
2368 P != PEnd; ++P)
2369 Diag(P->Partial->getLocation(), diag::note_partial_spec_match)
2370 << getTemplateArgumentBindingsText(
2371 P->Partial->getTemplateParameters(),
2372 *P->Args);
2373
2374 return true;
2375 }
2376 }
2377
2378 // Instantiate using the best class template partial specialization.
2379 ClassTemplatePartialSpecializationDecl *OrigPartialSpec = Best->Partial;
2380 while (OrigPartialSpec->getInstantiatedFromMember()) {
2381 // If we've found an explicit specialization of this class template,
2382 // stop here and use that as the pattern.
2383 if (OrigPartialSpec->isMemberSpecialization())
2384 break;
2385
2386 OrigPartialSpec = OrigPartialSpec->getInstantiatedFromMember();
2387 }
2388
2389 Pattern = OrigPartialSpec;
2390 ClassTemplateSpec->setInstantiationOf(Best->Partial, Best->Args);
2391 } else {
2392 // -- If no matches are found, the instantiation is generated
2393 // from the primary template.
2394 ClassTemplateDecl *OrigTemplate = Template;
2395 while (OrigTemplate->getInstantiatedFromMemberTemplate()) {
2396 // If we've found an explicit specialization of this class template,
2397 // stop here and use that as the pattern.
2398 if (OrigTemplate->isMemberSpecialization())
2399 break;
2400
2401 OrigTemplate = OrigTemplate->getInstantiatedFromMemberTemplate();
2402 }
2403
2404 Pattern = OrigTemplate->getTemplatedDecl();
2405 }
2406
2407 bool Result = InstantiateClass(PointOfInstantiation, ClassTemplateSpec,
2408 Pattern,
2409 getTemplateInstantiationArgs(ClassTemplateSpec),
2410 TSK,
2411 Complain);
2412
2413 return Result;
2414 }
2415
2416 /// \brief Instantiates the definitions of all of the member
2417 /// of the given class, which is an instantiation of a class template
2418 /// or a member class of a template.
2419 void
InstantiateClassMembers(SourceLocation PointOfInstantiation,CXXRecordDecl * Instantiation,const MultiLevelTemplateArgumentList & TemplateArgs,TemplateSpecializationKind TSK)2420 Sema::InstantiateClassMembers(SourceLocation PointOfInstantiation,
2421 CXXRecordDecl *Instantiation,
2422 const MultiLevelTemplateArgumentList &TemplateArgs,
2423 TemplateSpecializationKind TSK) {
2424 // FIXME: We need to notify the ASTMutationListener that we did all of these
2425 // things, in case we have an explicit instantiation definition in a PCM, a
2426 // module, or preamble, and the declaration is in an imported AST.
2427 assert(
2428 (TSK == TSK_ExplicitInstantiationDefinition ||
2429 TSK == TSK_ExplicitInstantiationDeclaration ||
2430 (TSK == TSK_ImplicitInstantiation && Instantiation->isLocalClass())) &&
2431 "Unexpected template specialization kind!");
2432 for (auto *D : Instantiation->decls()) {
2433 bool SuppressNew = false;
2434 if (auto *Function = dyn_cast<FunctionDecl>(D)) {
2435 if (FunctionDecl *Pattern
2436 = Function->getInstantiatedFromMemberFunction()) {
2437 MemberSpecializationInfo *MSInfo
2438 = Function->getMemberSpecializationInfo();
2439 assert(MSInfo && "No member specialization information?");
2440 if (MSInfo->getTemplateSpecializationKind()
2441 == TSK_ExplicitSpecialization)
2442 continue;
2443
2444 if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
2445 Function,
2446 MSInfo->getTemplateSpecializationKind(),
2447 MSInfo->getPointOfInstantiation(),
2448 SuppressNew) ||
2449 SuppressNew)
2450 continue;
2451
2452 // C++11 [temp.explicit]p8:
2453 // An explicit instantiation definition that names a class template
2454 // specialization explicitly instantiates the class template
2455 // specialization and is only an explicit instantiation definition
2456 // of members whose definition is visible at the point of
2457 // instantiation.
2458 if (TSK == TSK_ExplicitInstantiationDefinition && !Pattern->isDefined())
2459 continue;
2460
2461 Function->setTemplateSpecializationKind(TSK, PointOfInstantiation);
2462
2463 if (Function->isDefined()) {
2464 // Let the ASTConsumer know that this function has been explicitly
2465 // instantiated now, and its linkage might have changed.
2466 Consumer.HandleTopLevelDecl(DeclGroupRef(Function));
2467 } else if (TSK == TSK_ExplicitInstantiationDefinition) {
2468 InstantiateFunctionDefinition(PointOfInstantiation, Function);
2469 } else if (TSK == TSK_ImplicitInstantiation) {
2470 PendingLocalImplicitInstantiations.push_back(
2471 std::make_pair(Function, PointOfInstantiation));
2472 }
2473 }
2474 } else if (auto *Var = dyn_cast<VarDecl>(D)) {
2475 if (isa<VarTemplateSpecializationDecl>(Var))
2476 continue;
2477
2478 if (Var->isStaticDataMember()) {
2479 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo();
2480 assert(MSInfo && "No member specialization information?");
2481 if (MSInfo->getTemplateSpecializationKind()
2482 == TSK_ExplicitSpecialization)
2483 continue;
2484
2485 if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
2486 Var,
2487 MSInfo->getTemplateSpecializationKind(),
2488 MSInfo->getPointOfInstantiation(),
2489 SuppressNew) ||
2490 SuppressNew)
2491 continue;
2492
2493 if (TSK == TSK_ExplicitInstantiationDefinition) {
2494 // C++0x [temp.explicit]p8:
2495 // An explicit instantiation definition that names a class template
2496 // specialization explicitly instantiates the class template
2497 // specialization and is only an explicit instantiation definition
2498 // of members whose definition is visible at the point of
2499 // instantiation.
2500 if (!Var->getInstantiatedFromStaticDataMember()
2501 ->getOutOfLineDefinition())
2502 continue;
2503
2504 Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
2505 InstantiateStaticDataMemberDefinition(PointOfInstantiation, Var);
2506 } else {
2507 Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
2508 }
2509 }
2510 } else if (auto *Record = dyn_cast<CXXRecordDecl>(D)) {
2511 // Always skip the injected-class-name, along with any
2512 // redeclarations of nested classes, since both would cause us
2513 // to try to instantiate the members of a class twice.
2514 // Skip closure types; they'll get instantiated when we instantiate
2515 // the corresponding lambda-expression.
2516 if (Record->isInjectedClassName() || Record->getPreviousDecl() ||
2517 Record->isLambda())
2518 continue;
2519
2520 MemberSpecializationInfo *MSInfo = Record->getMemberSpecializationInfo();
2521 assert(MSInfo && "No member specialization information?");
2522
2523 if (MSInfo->getTemplateSpecializationKind()
2524 == TSK_ExplicitSpecialization)
2525 continue;
2526
2527 if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
2528 Record,
2529 MSInfo->getTemplateSpecializationKind(),
2530 MSInfo->getPointOfInstantiation(),
2531 SuppressNew) ||
2532 SuppressNew)
2533 continue;
2534
2535 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass();
2536 assert(Pattern && "Missing instantiated-from-template information");
2537
2538 if (!Record->getDefinition()) {
2539 if (!Pattern->getDefinition()) {
2540 // C++0x [temp.explicit]p8:
2541 // An explicit instantiation definition that names a class template
2542 // specialization explicitly instantiates the class template
2543 // specialization and is only an explicit instantiation definition
2544 // of members whose definition is visible at the point of
2545 // instantiation.
2546 if (TSK == TSK_ExplicitInstantiationDeclaration) {
2547 MSInfo->setTemplateSpecializationKind(TSK);
2548 MSInfo->setPointOfInstantiation(PointOfInstantiation);
2549 }
2550
2551 continue;
2552 }
2553
2554 InstantiateClass(PointOfInstantiation, Record, Pattern,
2555 TemplateArgs,
2556 TSK);
2557 } else {
2558 if (TSK == TSK_ExplicitInstantiationDefinition &&
2559 Record->getTemplateSpecializationKind() ==
2560 TSK_ExplicitInstantiationDeclaration) {
2561 Record->setTemplateSpecializationKind(TSK);
2562 MarkVTableUsed(PointOfInstantiation, Record, true);
2563 }
2564 }
2565
2566 Pattern = cast_or_null<CXXRecordDecl>(Record->getDefinition());
2567 if (Pattern)
2568 InstantiateClassMembers(PointOfInstantiation, Pattern, TemplateArgs,
2569 TSK);
2570 } else if (auto *Enum = dyn_cast<EnumDecl>(D)) {
2571 MemberSpecializationInfo *MSInfo = Enum->getMemberSpecializationInfo();
2572 assert(MSInfo && "No member specialization information?");
2573
2574 if (MSInfo->getTemplateSpecializationKind()
2575 == TSK_ExplicitSpecialization)
2576 continue;
2577
2578 if (CheckSpecializationInstantiationRedecl(
2579 PointOfInstantiation, TSK, Enum,
2580 MSInfo->getTemplateSpecializationKind(),
2581 MSInfo->getPointOfInstantiation(), SuppressNew) ||
2582 SuppressNew)
2583 continue;
2584
2585 if (Enum->getDefinition())
2586 continue;
2587
2588 EnumDecl *Pattern = Enum->getInstantiatedFromMemberEnum();
2589 assert(Pattern && "Missing instantiated-from-template information");
2590
2591 if (TSK == TSK_ExplicitInstantiationDefinition) {
2592 if (!Pattern->getDefinition())
2593 continue;
2594
2595 InstantiateEnum(PointOfInstantiation, Enum, Pattern, TemplateArgs, TSK);
2596 } else {
2597 MSInfo->setTemplateSpecializationKind(TSK);
2598 MSInfo->setPointOfInstantiation(PointOfInstantiation);
2599 }
2600 } else if (auto *Field = dyn_cast<FieldDecl>(D)) {
2601 // No need to instantiate in-class initializers during explicit
2602 // instantiation.
2603 if (Field->hasInClassInitializer() && TSK == TSK_ImplicitInstantiation) {
2604 CXXRecordDecl *ClassPattern =
2605 Instantiation->getTemplateInstantiationPattern();
2606 DeclContext::lookup_result Lookup =
2607 ClassPattern->lookup(Field->getDeclName());
2608 assert(Lookup.size() == 1);
2609 FieldDecl *Pattern = cast<FieldDecl>(Lookup[0]);
2610 InstantiateInClassInitializer(PointOfInstantiation, Field, Pattern,
2611 TemplateArgs);
2612 }
2613 }
2614 }
2615 }
2616
2617 /// \brief Instantiate the definitions of all of the members of the
2618 /// given class template specialization, which was named as part of an
2619 /// explicit instantiation.
2620 void
InstantiateClassTemplateSpecializationMembers(SourceLocation PointOfInstantiation,ClassTemplateSpecializationDecl * ClassTemplateSpec,TemplateSpecializationKind TSK)2621 Sema::InstantiateClassTemplateSpecializationMembers(
2622 SourceLocation PointOfInstantiation,
2623 ClassTemplateSpecializationDecl *ClassTemplateSpec,
2624 TemplateSpecializationKind TSK) {
2625 // C++0x [temp.explicit]p7:
2626 // An explicit instantiation that names a class template
2627 // specialization is an explicit instantion of the same kind
2628 // (declaration or definition) of each of its members (not
2629 // including members inherited from base classes) that has not
2630 // been previously explicitly specialized in the translation unit
2631 // containing the explicit instantiation, except as described
2632 // below.
2633 InstantiateClassMembers(PointOfInstantiation, ClassTemplateSpec,
2634 getTemplateInstantiationArgs(ClassTemplateSpec),
2635 TSK);
2636 }
2637
2638 StmtResult
SubstStmt(Stmt * S,const MultiLevelTemplateArgumentList & TemplateArgs)2639 Sema::SubstStmt(Stmt *S, const MultiLevelTemplateArgumentList &TemplateArgs) {
2640 if (!S)
2641 return S;
2642
2643 TemplateInstantiator Instantiator(*this, TemplateArgs,
2644 SourceLocation(),
2645 DeclarationName());
2646 return Instantiator.TransformStmt(S);
2647 }
2648
2649 ExprResult
SubstExpr(Expr * E,const MultiLevelTemplateArgumentList & TemplateArgs)2650 Sema::SubstExpr(Expr *E, const MultiLevelTemplateArgumentList &TemplateArgs) {
2651 if (!E)
2652 return E;
2653
2654 TemplateInstantiator Instantiator(*this, TemplateArgs,
2655 SourceLocation(),
2656 DeclarationName());
2657 return Instantiator.TransformExpr(E);
2658 }
2659
SubstInitializer(Expr * Init,const MultiLevelTemplateArgumentList & TemplateArgs,bool CXXDirectInit)2660 ExprResult Sema::SubstInitializer(Expr *Init,
2661 const MultiLevelTemplateArgumentList &TemplateArgs,
2662 bool CXXDirectInit) {
2663 TemplateInstantiator Instantiator(*this, TemplateArgs,
2664 SourceLocation(),
2665 DeclarationName());
2666 return Instantiator.TransformInitializer(Init, CXXDirectInit);
2667 }
2668
SubstExprs(Expr ** Exprs,unsigned NumExprs,bool IsCall,const MultiLevelTemplateArgumentList & TemplateArgs,SmallVectorImpl<Expr * > & Outputs)2669 bool Sema::SubstExprs(Expr **Exprs, unsigned NumExprs, bool IsCall,
2670 const MultiLevelTemplateArgumentList &TemplateArgs,
2671 SmallVectorImpl<Expr *> &Outputs) {
2672 if (NumExprs == 0)
2673 return false;
2674
2675 TemplateInstantiator Instantiator(*this, TemplateArgs,
2676 SourceLocation(),
2677 DeclarationName());
2678 return Instantiator.TransformExprs(Exprs, NumExprs, IsCall, Outputs);
2679 }
2680
2681 NestedNameSpecifierLoc
SubstNestedNameSpecifierLoc(NestedNameSpecifierLoc NNS,const MultiLevelTemplateArgumentList & TemplateArgs)2682 Sema::SubstNestedNameSpecifierLoc(NestedNameSpecifierLoc NNS,
2683 const MultiLevelTemplateArgumentList &TemplateArgs) {
2684 if (!NNS)
2685 return NestedNameSpecifierLoc();
2686
2687 TemplateInstantiator Instantiator(*this, TemplateArgs, NNS.getBeginLoc(),
2688 DeclarationName());
2689 return Instantiator.TransformNestedNameSpecifierLoc(NNS);
2690 }
2691
2692 /// \brief Do template substitution on declaration name info.
2693 DeclarationNameInfo
SubstDeclarationNameInfo(const DeclarationNameInfo & NameInfo,const MultiLevelTemplateArgumentList & TemplateArgs)2694 Sema::SubstDeclarationNameInfo(const DeclarationNameInfo &NameInfo,
2695 const MultiLevelTemplateArgumentList &TemplateArgs) {
2696 TemplateInstantiator Instantiator(*this, TemplateArgs, NameInfo.getLoc(),
2697 NameInfo.getName());
2698 return Instantiator.TransformDeclarationNameInfo(NameInfo);
2699 }
2700
2701 TemplateName
SubstTemplateName(NestedNameSpecifierLoc QualifierLoc,TemplateName Name,SourceLocation Loc,const MultiLevelTemplateArgumentList & TemplateArgs)2702 Sema::SubstTemplateName(NestedNameSpecifierLoc QualifierLoc,
2703 TemplateName Name, SourceLocation Loc,
2704 const MultiLevelTemplateArgumentList &TemplateArgs) {
2705 TemplateInstantiator Instantiator(*this, TemplateArgs, Loc,
2706 DeclarationName());
2707 CXXScopeSpec SS;
2708 SS.Adopt(QualifierLoc);
2709 return Instantiator.TransformTemplateName(SS, Name, Loc);
2710 }
2711
Subst(const TemplateArgumentLoc * Args,unsigned NumArgs,TemplateArgumentListInfo & Result,const MultiLevelTemplateArgumentList & TemplateArgs)2712 bool Sema::Subst(const TemplateArgumentLoc *Args, unsigned NumArgs,
2713 TemplateArgumentListInfo &Result,
2714 const MultiLevelTemplateArgumentList &TemplateArgs) {
2715 TemplateInstantiator Instantiator(*this, TemplateArgs, SourceLocation(),
2716 DeclarationName());
2717
2718 return Instantiator.TransformTemplateArguments(Args, NumArgs, Result);
2719 }
2720
getCanonicalParmVarDecl(const Decl * D)2721 static const Decl *getCanonicalParmVarDecl(const Decl *D) {
2722 // When storing ParmVarDecls in the local instantiation scope, we always
2723 // want to use the ParmVarDecl from the canonical function declaration,
2724 // since the map is then valid for any redeclaration or definition of that
2725 // function.
2726 if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(D)) {
2727 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(PV->getDeclContext())) {
2728 unsigned i = PV->getFunctionScopeIndex();
2729 // This parameter might be from a freestanding function type within the
2730 // function and isn't necessarily referring to one of FD's parameters.
2731 if (FD->getParamDecl(i) == PV)
2732 return FD->getCanonicalDecl()->getParamDecl(i);
2733 }
2734 }
2735 return D;
2736 }
2737
2738
2739 llvm::PointerUnion<Decl *, LocalInstantiationScope::DeclArgumentPack *> *
findInstantiationOf(const Decl * D)2740 LocalInstantiationScope::findInstantiationOf(const Decl *D) {
2741 D = getCanonicalParmVarDecl(D);
2742 for (LocalInstantiationScope *Current = this; Current;
2743 Current = Current->Outer) {
2744
2745 // Check if we found something within this scope.
2746 const Decl *CheckD = D;
2747 do {
2748 LocalDeclsMap::iterator Found = Current->LocalDecls.find(CheckD);
2749 if (Found != Current->LocalDecls.end())
2750 return &Found->second;
2751
2752 // If this is a tag declaration, it's possible that we need to look for
2753 // a previous declaration.
2754 if (const TagDecl *Tag = dyn_cast<TagDecl>(CheckD))
2755 CheckD = Tag->getPreviousDecl();
2756 else
2757 CheckD = nullptr;
2758 } while (CheckD);
2759
2760 // If we aren't combined with our outer scope, we're done.
2761 if (!Current->CombineWithOuterScope)
2762 break;
2763 }
2764
2765 // If we're performing a partial substitution during template argument
2766 // deduction, we may not have values for template parameters yet.
2767 if (isa<NonTypeTemplateParmDecl>(D) || isa<TemplateTypeParmDecl>(D) ||
2768 isa<TemplateTemplateParmDecl>(D))
2769 return nullptr;
2770
2771 // Local types referenced prior to definition may require instantiation.
2772 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D))
2773 if (RD->isLocalClass())
2774 return nullptr;
2775
2776 // Enumeration types referenced prior to definition may appear as a result of
2777 // error recovery.
2778 if (isa<EnumDecl>(D))
2779 return nullptr;
2780
2781 // If we didn't find the decl, then we either have a sema bug, or we have a
2782 // forward reference to a label declaration. Return null to indicate that
2783 // we have an uninstantiated label.
2784 assert(isa<LabelDecl>(D) && "declaration not instantiated in this scope");
2785 return nullptr;
2786 }
2787
InstantiatedLocal(const Decl * D,Decl * Inst)2788 void LocalInstantiationScope::InstantiatedLocal(const Decl *D, Decl *Inst) {
2789 D = getCanonicalParmVarDecl(D);
2790 llvm::PointerUnion<Decl *, DeclArgumentPack *> &Stored = LocalDecls[D];
2791 if (Stored.isNull()) {
2792 #ifndef NDEBUG
2793 // It should not be present in any surrounding scope either.
2794 LocalInstantiationScope *Current = this;
2795 while (Current->CombineWithOuterScope && Current->Outer) {
2796 Current = Current->Outer;
2797 assert(Current->LocalDecls.find(D) == Current->LocalDecls.end() &&
2798 "Instantiated local in inner and outer scopes");
2799 }
2800 #endif
2801 Stored = Inst;
2802 } else if (DeclArgumentPack *Pack = Stored.dyn_cast<DeclArgumentPack *>()) {
2803 Pack->push_back(cast<ParmVarDecl>(Inst));
2804 } else {
2805 assert(Stored.get<Decl *>() == Inst && "Already instantiated this local");
2806 }
2807 }
2808
InstantiatedLocalPackArg(const Decl * D,ParmVarDecl * Inst)2809 void LocalInstantiationScope::InstantiatedLocalPackArg(const Decl *D,
2810 ParmVarDecl *Inst) {
2811 D = getCanonicalParmVarDecl(D);
2812 DeclArgumentPack *Pack = LocalDecls[D].get<DeclArgumentPack *>();
2813 Pack->push_back(Inst);
2814 }
2815
MakeInstantiatedLocalArgPack(const Decl * D)2816 void LocalInstantiationScope::MakeInstantiatedLocalArgPack(const Decl *D) {
2817 #ifndef NDEBUG
2818 // This should be the first time we've been told about this decl.
2819 for (LocalInstantiationScope *Current = this;
2820 Current && Current->CombineWithOuterScope; Current = Current->Outer)
2821 assert(Current->LocalDecls.find(D) == Current->LocalDecls.end() &&
2822 "Creating local pack after instantiation of local");
2823 #endif
2824
2825 D = getCanonicalParmVarDecl(D);
2826 llvm::PointerUnion<Decl *, DeclArgumentPack *> &Stored = LocalDecls[D];
2827 DeclArgumentPack *Pack = new DeclArgumentPack;
2828 Stored = Pack;
2829 ArgumentPacks.push_back(Pack);
2830 }
2831
SetPartiallySubstitutedPack(NamedDecl * Pack,const TemplateArgument * ExplicitArgs,unsigned NumExplicitArgs)2832 void LocalInstantiationScope::SetPartiallySubstitutedPack(NamedDecl *Pack,
2833 const TemplateArgument *ExplicitArgs,
2834 unsigned NumExplicitArgs) {
2835 assert((!PartiallySubstitutedPack || PartiallySubstitutedPack == Pack) &&
2836 "Already have a partially-substituted pack");
2837 assert((!PartiallySubstitutedPack
2838 || NumArgsInPartiallySubstitutedPack == NumExplicitArgs) &&
2839 "Wrong number of arguments in partially-substituted pack");
2840 PartiallySubstitutedPack = Pack;
2841 ArgsInPartiallySubstitutedPack = ExplicitArgs;
2842 NumArgsInPartiallySubstitutedPack = NumExplicitArgs;
2843 }
2844
getPartiallySubstitutedPack(const TemplateArgument ** ExplicitArgs,unsigned * NumExplicitArgs) const2845 NamedDecl *LocalInstantiationScope::getPartiallySubstitutedPack(
2846 const TemplateArgument **ExplicitArgs,
2847 unsigned *NumExplicitArgs) const {
2848 if (ExplicitArgs)
2849 *ExplicitArgs = nullptr;
2850 if (NumExplicitArgs)
2851 *NumExplicitArgs = 0;
2852
2853 for (const LocalInstantiationScope *Current = this; Current;
2854 Current = Current->Outer) {
2855 if (Current->PartiallySubstitutedPack) {
2856 if (ExplicitArgs)
2857 *ExplicitArgs = Current->ArgsInPartiallySubstitutedPack;
2858 if (NumExplicitArgs)
2859 *NumExplicitArgs = Current->NumArgsInPartiallySubstitutedPack;
2860
2861 return Current->PartiallySubstitutedPack;
2862 }
2863
2864 if (!Current->CombineWithOuterScope)
2865 break;
2866 }
2867
2868 return nullptr;
2869 }
2870